Occidently re-orienting atoms

It seems atoms are not quite as chemists imagine them not to be

Keith S. Taber

A research paper presenting a new model of atomic and molecular structure was recently brought to my attention. 1

The paper header

'New Atomic Model with Identical Electrons Position in the Orbital's and Modification of Chemical Bonds and MOT [molecular orbital theory]' 2 is published in a recently-launched journal with the impressive title of Annals of Atoms and Molecules. This is an open-access journal available free on the web – so readily accessible to chemistry experts, as well as students studying the subject and lay-people looking to learn from a scholarly source. [Spoiler alert – it may not be an ideal source for scholarly information!]

In the paper, Dr Morshed proposes a new model of the atom that he suggests overcomes many problems with the model currently used in chemistry.

A new model of atomic structure envisages East and West poles as well as North and South poles) (Morshed, 2020a, p.8)

Of course, as I have often pointed out on this blog, one of the downsides of the explosion in on-line publishing and the move to open access models of publication, is that anyone can set up as an academic journal publisher and it can be hard for the non-expert to know what reflects genuine academic quality when what gets published in many new journals often seems to depend primarily upon an author being willing to pay the publisher a hefty fee (Taber, 2013).

That is not to suggest open-access publishing has to compromise quality: the well-established, recognised-as-prestigious journals can afford to charge many hundreds of pounds for open-access publication and still be selective. But, new journals, often unable to persuade experienced experts to act as reviewers, will not attract many quality papers, and so cannot be very selective if they are to cover costs (or indeed make the hoped-for profits for their publishers).

A peer reviewed journal

The journal with the impressive title of Annals of Atom and Molecules has a website which explains that

"Annals of Atoms and Molecules is an open access, peer reviewed journal that publishes novel research insights covering but not limited to constituents of atoms, isotopes of an element, models of atoms and molecules, excitations and de-excitations, ionizations, radiation laws, temperatures and characteristic wavelengths of atoms and molecules. All the published manuscripts are subjected to standardized peer review processing".

https://scholars.direct/journal.php?jid=atoms-and-molecules

So, in principle at least, the journal has experts in the field critique submissions, and advise the editors on (i) whether a manuscript has potential to be of sufficient interest and quality to be worth publishing, and (ii) if so, what changes might be needed before publications is wise.

Read about peer review

Standardised peer review gives the impression of some kind of moderation (perhaps renormalisation given the focus of the journal? 3) of review reports, which would involve a lot of extra work and another layer of administration in the review process…but I somehow suspect this claim really just meant a 'standard' process. This does not seem to be a journal where great care is taken over the language used.

Effective peer review relies on suitable experts taking on the reviewing, and editors prepared to act on their recommendations. The website lists five members of the editorial board, most of whom seem to be associated with science departments in academic institutions:

  • Prof. Farid Menaa (Fluorotronics Inc) 4
  • Prof. Sabrin Ragab Mohamed Ibrahim (Department of Pharmacognosy and Pharmaceutical chemistry, Taibah University)
  • Prof. Mina Yoon (Department of Physics and Astronomy, University of Tennessee)
  • Dr. Christian G Parigger (Department of Physics, University of Tennessee Space Institute)
  • Dr. Essam Hammam El-Behaedi (Department of Chemistry and Biochemistry, University of North Carolina Wilmington)

The members of a journal Editorial Board will not necessarily undertake the reviewing themselves, but are the people entrusted by the publisher with scholarly oversight of the quality of the journal. For this journal it is claimed that "Initially the editorial board member handles the manuscript and may assign or the editorial staff may assign the reviewers for the received manuscript". This sounds promising, as at least (it is claimed) all submissions are initially seen by a Board member, whether or not they actually select the expert reviewers. (The 'or' means that the claim is, of course, logically true even if in actuality all of the reviewers are assigned by the unidentified office staff.)

At the time of writing only three papers have been published in the Annals. One reviews a spectroscopic method, one is a short essay on quantum ideas in chemistry – and then there is Dr Morshed's new atomic theory.

A new theory of atomic structure

The abstract of Dr Morshed's paper immediately suggests that this is a manuscript which was either not carefully prepared or has been mistreated in production. The first sentence is:

The concept of atom has undergone numerous changes in the history of chemistry, most notably the realization that atoms are divisible and have internal structure Scientists have known about atoms long before they could produce images of them with powerful magnifying tools because atoms could not be seen, the early ideas about atoms were mostly founded in philosophical and religion-based reasoning.

Morshed, 2020a, p.6

Presumably, this was intended to be more than one sentence. If the author made errors in the text, they should have been queried by the copy editor. If the production department introduced errors, then they should have been corrected by the author when sent the proofs for checking. Of course, a few errors can sometimes still slip through, but this paper has many of them. Precise language is important in a research paper, and sloppy errors do not give the reader confidence in the work being reported.

The novelty of the work is also set out in the abstract:

In my new atomic model, I have presented the definite position of electron/electron pairs in the different orbital (energy shells) with the identical distance among all nearby electron pairs and the degree position of electrons/electron pairs with the Center Point of Atoms (nucleus) in atomic structure, also in the molecular orbital.

Morshed, 2020a, p.6

This suggests more serious issues with the submission than simple typographical errors.

Orbital /energy shells

The term "orbital (energy shells)" is an obvious red flag to any chemist asked to evaluate this paper. There are serious philosophical arguments about precisely what a model is and the extent to which a model of the atom might be considered to be realistic. Arguably, models that are not mathematical and which rely on visualising the atom are inherently not realistic as atoms are not the kinds of things one could see. So, terms such as shell or orbital are either being used to refer to some feature in a mathematical description or are to some extent metaphorical. BUT, when the term shell is used, it conventionally means something different from an orbital.

That is, in the chemical community, the electron shell (sic, not energy shell) and the orbital refer to different classes of entity (even if in the case of the K shell there is only one associated orbital). Energy levels are related, but again somewhat distinct – an energy level is ontologically quite different to an orbital or a shell in a similar way to how sea level is very different in kind to a harbour or a lagoon; or how 'mains voltage' is quite different from the house's distribution box or mains ring; or how an IQ measurement is a different kind of thing to the brain of the person being assessed.

Definite positions of electrons

An orbital is often understood as a description of the distribution of the electron density – we might picture (bearing in mind my point that the most authentic models are mathematical) the electron smeared out as in a kind of time-lapse representation of where the electron moves around the volume of space designated as an orbital. Although, as an entity small enough for quantum effects to be significant (a 'quanticle'? – with some wave-like characteristics, rather than a particle that is just like a bearing ball only much smaller), it may be better not to think of the electron actually being at any specific point in space, but rather having different probabilities of being located at specific points if we could detect precisely where it was at any moment.

That is, if one wants to consider the electron as being at specific points in space then this can only be done probabilistically. The notion of "the definite position of electron/electron pairs in the different orbital" is simply nonsensical when the orbital is understood in terms of a wave function. Any expert asked to review this manuscript would surely have been troubled by this description.

It is often said that electrons are sometimes particles and sometimes waves but that is a very anthropocentric view deriving from how at the scale humans experience the world, these seem very distinct types of things. Perhaps it is better to think that electrons are neither particles nor waves as we experience them, but something else (quanticles) with more subtle behavioural repertoires. We think that there is a fundamental inherent fuzziness to matter at the scale where we describe atoms and molecules.

So, Dr Morshed wants to define 'definite positions' for electrons in his model, but electrons in atoms do not have a fixed position. (Later there is reference to circulation – so perhaps these are considered as definite relative positions?) In any case, due to the inherent fuzziness in matter, if an electron's position was known absolutely then there would would (by the Heisenberg uncertainty principle) be an infinite uncertainty in its momentum, so although we might know 'exactly' where it was 'now' (or rather 'just now' when the measurement occurred as it would take time for the signal to be processed through first our laboratory, and then our nervous, apparatus!) this would come with having little idea where it was a moment later. Over any duration of time, the electron in an atom does not have a definite position – so there is little value in any model that seeks to represent such a fixed position.

The problem addressed

Dr Morshed begins by giving some general historical introduction to ideas about the atom, before going on to set out what is argued to be the limitation of current theory:

Electrons are arranged in different orbital[s] by different numbers in pairs/unpaired around the nuclei. Electrons pairs are associated by opposite spin together to restrict opposite movement for stability in orbital rather angular movements. The structural description is obeyed for the last more than hundred years but the exact positions of electrons/pairs in the energy shells of atomic orbital are not described with the exact locations among different orbital/shells.

Morshed, 2020a, p.6

Some of this is incoherent. It may well be that English is not Dr Morshed's native language, in which case it is understandable that producing clear English prose may be challenging. What is less forgivable is that whichever of Profs. Ibrahim, Yoon, or Drs Menaa, Parigger, or El-Behaedi initially handled the manuscript did not point out that it needed to be corrected and in clear English before it could be considered for publication, which could have helped the author avoid the ignominy of having his work published with so many errors.

That assumes, of course, that whichever of Ibrahim, Yoon, Menaa, Parigger, or El-Behaedi initially handled the manuscript were so ignorant of chemistry to be excused for not spotting that a paper addressing the issue of how current atomic models fail to assign "exact positions of electrons/pairs in the energy shells of atomic orbital are not described with the exact locations among different orbital/shells" both confused distinct basic atomic concepts and seemed to be criticising a model of atomic structure that students move beyond before completing upper secondary chemistry. In other words, this paper should have been rejected on editorial screening, and never should have been sent to review, as its basic premise was inconsistent with modern chemical theory.

If, as claimed, all papers are seen by the one of the editorial board, then the person assigned as handling editor for this one does not seem to have taken the job seriously. (And as only three papers have been published since the journal started, the workload shared among five board members does not seem especially onerous.)

Just in case the handling editorial board member was not reading the text closely enough, Dr Morshed offered some images of the atomic model which is being critiqued as inadequate in the paper:

A model of the atom criticised in the paper in Annals of Atoms and Molecules (Morshed, 2020a, p.7)

I should point out that I am able to reproduce material from this paper as it is claimed as copyright of the author who has chosen to publish open access with a license that "permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited". (Although, if you look very closely at the first figure, it seems to have superimposed in red text "© Copyright www.chemistrytutotial.org", where, by an unlikely coincidence, I found what seems to be the same image on the page Atomic Structure with Examples.)

Read about copyright in academic works

Again, the handling editor should have noticed that these images in the figure reflect the basic model of the atom taught in introductory school classes as commonly represented in simple two-dimensional images. These are not the models used to progress knowledge in academic chemistry today.

These images are not being reproduced in the research paper as part of some discussion of atomic representations in school textbooks. Rather this is the model that the author is suggesting falls short as part of current chemical theory – but it is actually an introductory pedagogical model that is not the basis of any contemporary chemical research, and indeed has not been so for the best part of a century. Even though the expression "the electrons/electron pairs position is not identical by their position, alignments or distribution" does not have any clear meaning in normal English, what is clear is that these very simple models are only used today for introductory pedagogic purposes.

Symmetrical atoms?

The criticism of the model continues:

The existing electrons pair coupling model is not also shown clearly in figure by which a clear structure of opposite spine pair can be drowned. Also there are no proper distribution of electron/s around the center (nuclei) to maintain equal number of electrons/electronic charge (charge proportionality) around the total mass area of atomic circle (360°) in the existing atomic model (Figure 1). There are no clear ideas about the speed proportion and time of circulation of electrons/electron pairs in the atomic orbital/shells so there is no answer about the possibility of uneven number of electrons/electron pairs at any position /side of atomic body can arise that must make any atom unstable.

Morshed, 2020a, p.7

Again, this makes little sense (to me at least – perhaps the Editorial Board members are better at hermeneutics than I am). Now we are told that electrons are 'circulating' in the orbitals/shell which seems inconsistent with them having the "definite positions" that Dr Morshed's model supposedly offers. Although I can have a guess at some of the intended meaning, I really would love to know what is meant by "a clear structure of opposite spine pair can be drowned".

Protecting an atom from drowning? (Images by Image by ZedH  and  Clker-Free-Vector-Images from Pixabay)
A flat model of the atom

I initially thought that Dr Morshed is concerned that the model shown in figure 1 cannot effectively show how in the three dimensional atomic structure the electrons must be arranged to give a totally symmetric patterns: and (in his argument) that this would be needed else it would leave the atoms unstable. Of course, two dimensional images do not easily show three dimensional structure. So when Dr Morshed referred to the "atomic circle (360°) in the existing atomic model" I assumed he was actually referring to the sphere.

On reflection, I am not so sure. I was unimpressed by the introduction of cardinal points for the atom (see Dr Morshed's figure 2 above, and figure 4 below). I could understand the idea of a nominal North and South pole in relation to the angular momentum of the nucleus and electrons 'spinning up or down' – but surely the East and West poles are completely arbitrary for an atom as any point on the 'equator' could be used as the basis for assigning these poles. However, if Dr Morshed is actually thinking in terms of a circular (i.e., flat) model of the atom, and not circular representations of a spherical model of atomic structure then atoms would indeed have an Occident and an Orient! The East pole WOULD be to the right when the atom has the North pole at the top as is conventional in most maps today. 5

But atoms are not all symmetrical?

But surely most atoms are not fully symmetrical, and indeed this is linked to why most elements do not commonly exist as discrete atoms. The elements of those that do, the noble gas elements, are renown for not readily reacting because they (atypically for atoms) have a symmetrical electronic 'shield' for the nuclear charge. However, even some of these elements can be made cold enough to solidify – as the van der Waals forces allow transient fluctuating dipoles. So the argument seems to be based on a serious alternative conception of the usual models of atomic structure.

It is the lack of full symmetry in an atom of say, fluorine, or chlorine, which means that although it is a neutral species it has an electron affinity (that is, energy is released when the anion is formed) as an electron can be attracted to the core charge where it is not fully shielded.

The reference to "time of circulation of electrons/electron pairs in the atomic orbital/shells" seems to refer to a mechanical model of orbital motion, which again, has no part in current chemical theory.

Preventing negative electron pairs repelling each other

Dr Morshed suggests that the existing model of atomic structure cannot explain

Why the similar charged electrons don't feel repulsion among themselves within the same nearby atomic orbital of same atom or even in the molecular orbital when two or more atomic orbital come closer to form molecular orbital within tinier space though there is more possibility of repulsion between similar charged electrons according to existing atomic model.

Morshed, 2020a, p.7

Electrons do not feel repulsion for the same reason they do not feel shame or hunger or boredom – or disdain for poor quality journals. Electrons are not the kind of objects that can feel anything. However, this anthropomorphic expression is clearly being used metaphorically.

I think Dr Morshed is suggesting that the conventional models of atomic structure do not explain why electrons/electron pairs do not repel each other. Of course, they do repel each other – so there is no need to look for an explanation. This then seems to be an alternative conception of current models of the atom. (The electrons do not get ejected from the atom as they are also attracted to the nucleus – but, if they did not repel each other, there would be no equilibrium of forces, and the structure of the atom would not be stable.)

A new model of atomic structure supposedly reflects the 'proper' angles between electrons in atoms (Morshed, 2020, p.9)

Dr Morshed suggests that his model (see his Figure 4) 'proves the impossibility of repulsion between any electron pairs' – even those with similar charges. All electron pairs have negative (so similar) charges – it is part of the accepted definition of an electron that is is a negatively charged entity. I do not think Dr Morshed is actually suggesting otherwise, even if he thinks the electrons in different atoms have different magnitudes of negative charge (Morshad, 2020b).

Dr Morshed introduces a new concept that he calls 'center of electron pairs neutralization point'.

This is the pin-point situated in a middle position between two electrons of opposite spin pairs. The point is exactly between of opposite spine electron pairs so how the opposite electronic spin is neutralized to remaining a stable electron pair consisting of two opposite spin electrons. This CENP points are assumed to be situated between the cross section of opposite spine electronic pair's magnetic momentum field diameter (Figure 3).

Morshed, 2020a, p.8
The yellow dot represents a point able to neutralise the opposite spin of a pair of electrons(!), and is located at the point found by drawing a cross from the ends of the ⥯ symbols used to show the electron spin! This seems to be envisaged a real point that has real effects, despite being located in terms of the geometry of a totally arbitrary symbol.

So, the electron pair is shown as a closely bound pair of electrons with the midspot of the complex highlighted (yellow in the figure) as the 'center of electron pairs neutralization point'. Although the angular momentum of the electrons with opposite spin leads to a magnetic interaction between them, they are still giving rise to an electric field which permeates through the space around them. Dr Morshed seems to be suggesting that in his model there is no repulsion between the electron pairs. He argues that:

According to magnetic attraction/repulsion characteristics any similar charges repulse or opposite charges attract when the charges energy line is in straight points. If similar charged or opposite charged end are even close but their center of energy points is not in straight line, there will be no attraction or repulsion between the charges (positive/negative). Similarly, when electrons are arranged in energy shells around the nucleus the electrons remain in pairs within opposite spin electrons where the poses a point which represent as the center of repulsion/attraction points (CENP) and two CENP never come to a straight within the atomic orbital so the similar charged electrons pairs don't feel repulsion within the energy shells.

Morshed, 2020a, pp.8-9

A literal reading of this makes little sense as any two charges will always have their centres in a straight line (from the definition of a straight line!) regardless of whether similar or opposite charges or whether close or far apart.

My best interpretation of this (and I am happy to hear a better one) is that because the atom is flat, and because the electron pairs have spin up and spin down electrons, with are represented by a kind of ⥮ symbol, the electrons in some way shield the 'CENP' so that the electron pair can only interact with another charge that has a direct line of sight to the CENP.

Morshed seems to be suggesting that although electron pairs are aligned to allow attractions with the nucleus (e.g., blue arrows) any repulsion between electron pairs is blocked because an electron in the pair shields the central point of the pair (e.g., red arrow and lines)

There are some obvious problems here from a canonical perspective, even leaving aside the flat model of the atom. One issue is that although electrons are sometimes represented as or ⇂ to indicate spin, electrons are not actually physically shaped like . Secondly, pairing allows electrons to occupy the same orbital (that is, have the same set of principal, azimuthal and magnetic quantum numbers) – but this does not mean they are meant to be fixed into a closely bound entity. Also, this model works by taking the idea of spin direction literally, when – if we do that – electrons can have only have spin of ±1/2. In a literal representation such as used by Dr Morshed he would need to have ALL his electrons orientated vertically (or at least all at the same angle from the vertical). So, the model does not work in its own terms as it would prevent most of the electron pairs being attracted to the nucleus.

Morshed's figure 4 'corrected' given that electrons can only exist in two spin states. In the (corrected version of the representation of the) Morshed model most electron pairs would not be attracted to the nucleus.

A new (mis)conception of ionic bonding

Dr Morshed argues that

In case of ionic compound formation problem with the existing atomic model is where the transferred electron will take position in the new location on transferred atom? If the electrons position is not proportionally distributed along total 360 circulating area of atom, then the position of new transferred electron will cause the polarity in every ion (both cation and anion forms by every transformation of electrons) so the desired ionization is not possible thus every atom (ion) would become dipolar. On the point of view any ionization would not possible i.e., no ionic bonded compound would have formed.

Morshed, 2020, p.7

Again, although the argument may have been very clear to the author, this seems incoherent to a reader. I think Dr Morshed may be arguing that unless atoms have totally symmetrical electrons distributions ("proportionally distributed along total 360 circulating area of atom") then when the ion is formed it will have a polarity. Yet, this seems entirely back to front.

If the atom to be ionised was totally symmetric (as Dr Morshed thinks it should be), then forming an ion from the atom would require disrupting the symmetry. Whereas, by contrast, in the current canonical model, we assume most atoms are not symmetrical, and the formation of simple ions leads to a symmetric distribution of electrons (but unlike in the noble gas atoms, a symmetrical electron distribution which does not balance the nuclear charge).

Dr Morshad illustrates his idea:

Ionic bond formation represented by an non-viable interaction between atoms (Morshed, 2020, p.10)

Now these images show interactions between discrete atoms (a chemically quite unlikely scenario, as discrete atoms of sodium and chlorine are not readily found) that are energetically non-viable. As has often been pointed out, the energy released when the chloride ion is formed is much less than the energy required to ionise the sodium atom, so although this scheme is very common on the web and in poor quality textbooks, it is a kind of chemical fairy tale that does not relate to any likely chemical context. (See, for example, Salt is like two atoms joined together.)

The only obvious difference between these two versions of the fairly tale (if we ignore that in the new version both protons and neutrons appear to be indicated by + signs which is unhelpful) seems to be that the transferred electron changes its spin for some reason that does not seem to be explained in the accompanying text. The explanation that is given is

My new atomic model with identical electrons pair angle position is able to give logical solution to the problems of ion/ionic bond formation. As follows: The metallic atom which donate electrons during ion formation from outermost orbital, the electrons are arranged maintaining definite degree angle around 360° atomic mass body shown in (Figure 4). After the transformation the transferred electron take position at the vacant place of the transferred atoms outermost orbital, then instant the near most electrons/pairs rearrange their position in the orbital changing their angle position with the CPA [central point of the atom, i.e., the nucleus] due to electromagnetic repulsion feeling among the similar charged electrons/pairs. Thus the ionic atom gets equal electron charge density around whole of their 360° atomic mass body resulting the cation and anion due to the positive and negative charge difference in atomic orbital with their respective nucleus. Thus every ion becomes non polar ion to form ionic bond within two opposite charged ion (Figure 5).

Morshed, 2020, p.9

So, I think, supposedly part (b) of Dr Morshed's figure 5 is meant to show, better than part (a), how the electron distribution is modified when the ion is formed. It would of course be quite possible to show this in the kind of representations used in (a), but in any case it does not look any more obvious in (b) to my eye!

So, figure 5 does not seem to show very well Dr Morshed's solution to a problem I do not think actually exists in the context on a non-viable chemical process. Hm.

Finding space for the forces

Another problem with the conventional models, according to Dr Morshed, is that, as suggested in his figures 6 and 7 is that the current models do not leave space for the 'intermolecular' [sic, intramolecular] force of attraction in covalent bonds.

In current models, according to Morshed's paper, electrons get in the way of the covalent bond (Morshed, 2020, p.11)

Dr Morshad writes that

According to present structural presentation of shared paired electrons remain at the juncture of the bonded atomic orbital, if they remain like such position they will restrict the Inter [sic] Molecular Force (IMF) between the bonded atomic nuclei because the shared paired electron restricts the attraction force lying at the straight attraction line of the bonded nuclei the shown in (Figure 6a).

Morshed, 2020, p.11

There seem to be several alternative conceptions operating here – reflecting some of the kind of confusions reported in the literature from studies on students' ideas.

  1. Just because the images are static two dimensional representations, this does not mean electrons are envisaged to be stationary at some point on a shell;
  2. and just because we draw representations of atoms on flat paper, this does not mean atoms are flat;
  3. The figure is meant to represent the bond, which is an overall configuration of the nuclei and the electrons, so there is not a distinct intramolecular force operating separately;
  4. Without the electrons there would be no "Inter [sic] Molecular Force (IMF) between the bonded atomic nuclei" as the nuclei repel each other: the bonding electrons do not restrict the intramolecular force (blocking it, because they lie between the nuclei), but are crucial to it existing.

Regarding the first point here, Dr Morshed suggests

Covalent bonds are formed by sharing of electrons between the bonded atoms and the shared paired electrons are formed by contribution of one electron each of the participating atoms. The shared paired electrons remain at the overlapping chamber (at the juncture of the overlapped atomic orbital).

Morshed, 2020, p.9

That is, according to Dr Morshed's account of current atomic theory, in drawing overlapping electron shells, the electrons of the bond which are 'shared' (and that is just a metaphor, of course) are limited to the area shown as overlapping. This is treating an abstract and simplistic representation as if it is realistic. There is no chamber. Indeed, the molecular orbital formed by the overlap of the atomic orbitals will 'allow' the electrons to be likely to be found within quite a (relatively – on an atomic scale) large volume of space around the bond axis. Atomic orbitals that overlap to form molecular orbitals are in effect replaced by those molecular orbitals – the new orbital geometry reflects the new wavefunction that takes into account both electrons in the orbital.

So, if there has been overlap, the contributing atomic orbitals should be considered to have been replaced (not simply formed a chamber where the circles overlap), except of course Dr Morshed 's figures 6 and 7 show shells and do not actually represent the system of atomic orbitals.

Double bonds

This same failure to interpret the intentions and limitation of the simplistic form of representation used in introductory school chemistry leads to similar issues when Dr Morshed considers double bonding.

A new model of atomic structure suggests an odd geometry for pi bonds (Morshed, 2020, p.12)

Dr Morshed objects to the kind of representation on the left in his figure 8 as two electron pairs occupy the same area of overlap ('chamber'),

It is shown for an Oxygen molecule; two electron shared pairs are formed and take place at the overlapping chamber result from the outermost orbital of two bonded Oxygen atoms. But in real séance [sic?] that is impossible because two shared paired electrons cannot remain in a single overlapping chamber because of repulsion among each pairs and among individual electrons.

Morshed, 2020, p.12.

Yet, in the model Dr Morshed employs he had claimed that electron pairs do not repel unless they are aligned to allow a direct line of sight between their CNPs. In any case, the figure he criticises does not show overlapping orbitals, but overlapping L shells. He suggests that the existing models (which of course are not models currently used in chemistry except in introductory classes) imply the double bond in oxygen must be two sigma bonds: "The present structure of O2 molecule show only two pairs of electron with head to head overlapping in the overlapping chamber i.e., two sigma bond together which is impossible" (p.12).

However, this is because a shell type presentation is being used which is suitable for considering whether a bond is single or double (or triple), but no more. In order to discuss sigma and pi bonds with their geometrical and symmetry characteristics, one must work with orbitals, not shells. 6

Yet Dr Morshed has conflated shells and orbitals throughout his paper. His figure 8a that supposedly shows "Present molecular orbital structural showing two shared paired electrons in the same overlapped chamber" does not represent (atomic, let alone molecular) orbitals, and is not intended to suggest that the space between overlapping circles is some kind of chamber.

"The remaining two opposite spin unpaired electrons in the two bonded [sic?] Oxygen's outer- most orbital [sic, shell?] getting little distorted towards the shared paired electrons in their respective atomic orbital then they feel an attraction among the opposite spin electrons thus they make a bond pairs by side to side overlapping forms the pi-bond"

Morshed, 2020, p.12.

It is not at all clear to see how this overlap occurs in this representation (i.e., 8b). Moreover, the unpaired electrons will not "feel an attraction" as they are both negatively charged even if they have anti-parallel spins. The scheme also makes it very difficult to see how the pi bond could have the right symmetry around the bond axis, if the 'new molecular orbital structure' was taken at face value.

Conclusion

Dr Morshed's paper is clearly well meant, but it does not offer any useful new ideas to progress chemistry. It is highly flawed. There is no shame in producing highly flawed manuscripts – no one is perfect, which is why we have peer review to support authors in pointing out weaknesses and mistakes in their work and so allowing them to develop their ideas till they are suitable for publication. Dr Morshed has been badly let down by the publishers and editors of Annals of Atoms and Molecules. I wonder how much he was charged for this lack of service? 7

Publishing a journal paper like this, which is clearly not ready to make a contribution to the scholarly community through publication, does not only do a disservice to the author (who will have this publication in the public domain for anyone to evaluate) but can potentially confuse or mislead students who come across the journal. Confusing shells with orbitals, misrepresenting how ionic bonds form, implying that covalent bonds are due to a force between nuclei, suggesting that electron pairs need not repel each other, suggesting a flat model of the atom with four poles… there are many points in this paper that can initiate or reinforce student misconceptions.

Supposedly, this manuscript was handled by a member of the editorial board, sent to peer reviewers and the publication decision based on those review reports. It is hard to imagine any peer reviewer who is actually an academic chemist (let alone an expert in the topics published in this journal) considering this paper would be publishable, even with extensive major revisions. The whole premise of the paper (that simple representations of atoms with concentric shells of electrons reflect the models of atomic and molecular structure used today in chemistry research) is fundamentally flawed. So:

  • were there actually any reviews? (Really?)
  • if so, were the reviews carried out by experts in the field? (Or even graduate chemists or physicists?)
  • were the reviews positive enough to justify publication?

If the journal feels I am being unfair, then I am happy to publish any response submitted as a comment below.

Dr Menaa, Prof. Ibrahim, Prof. Yoon, Dr Parigger, Dr El-Behaedi…

If you were the Board Member who handled this submission and you feel my criticisms are unfair, please feel free to submit a comment. I am happy to publish your response.

Or, if you were not the Board Member who (allegedly) handled this submission, and would like to make that clear…

Works cited:
Note:

1 I thank Professor Eric Scerri of UCLA for bringing my attention to the deliciously named 'Annals of Atoms and Molecules', and this specific contribution.

2 That is my reading of the abbreviation, although the author uses the term a number of times before rather imprecisely defining it: "Similar solution can be made for molecular orbital (MOT) as such as: The molecular orbital (MO) theory…" (p.10).

3 Renormalisation is the name given to a set of mathematical techniques used in areas such as quantum field theory when calculations give implausible infinite results in order to 'lose' the unwanted infinities. Whilst this might seem like cheating – it is tolerated as it works very well.

4 I was intrigued that 'Prof.' Farid Menaa seemed to work for a non-academic institution, as generally companies cannot award the title of Professor. Of course, Prof. Meena may also have an appointment at a university that partners the company, or could have emeritus status having retired from academia.

I found him profiled on another publisher's site as "Professor, Principal Investigator, Director, Consultant Editor, Reviewer, Event Organizer and Entrepreneur,…" who had worked in oncology, dermatology, haemotology (when "he pioneered new genetic variants of stroke in sickle cell anemia patients" which presumably is much more positive than it reads). Reading on, I found he had 'followed' complementary formations in "Medecine [sic], Pharmacy, Biology, Biochemistry, Food Sciences and Technology, Marine Biology, Chemistry, Physics, Nano-Biotechnology, Bio-Computation, and Bio-Statistics" and was "involved in various R&D projects in multiple areas of medicine, pharmacy, biology, genetics, genomics, chemistry, biophysics, food science, and technology". All of which seemed very impressive (nearly as wide a range of expertise as predatory journal publishers claim for me), but made me none the wiser about the source of his Professorial title.

5 Today. Although interestingly, in the first major comprehensive account of magnetism, Gilbert (1600/2016) tended to draw the North-South axis of the earth horizontally in his figures.

6 The representations we draw are simple depictions of something more subtle. If the circles did represent orbitals then they could not show the entire volume of space where the electron might be found (as this is theoretically infinite) but rather an envelope enclosing a volume where there is the highest probability (or 'electron density'). So orbitals will actually overlap to some extent even when simple images suggest otherwise.

7 I wonder because the appropriate page, https://scholars.direct/publication-charges.php, "was not found on this server" when I looked to see.

A tangible user interface for teaching fairy tales about chemical bonding

Keith S. Taber

Image by S. Hermann & F. Richter from Pixabay
Once upon a time there was a nometal atom that was an electron short of a full outer shell. "I wish I had an octet" she said, "if only I knew a nice metal atom that might donate their extra electron to me"… Image by S. Hermann & F. Richter from Pixabay

 

Today I received one of those internet notifications intended to alert you to work that you might want to read:

"You wrote the paper A common core to chemical conceptions: learners' conceptions of chemical…. A related paper is available on Academia.

Tangible interaction approach for learning chemical bonding"

an invitation to read
An invitation to read

I was intrigued. Learning (and teaching) about chemical bonding concepts has been a long-standing interest of mine, and I have written quite a lot on the topic, so I clicked-through and downloaded the paper.

The abstract began

"In this paper we present ChemicAble, a Tangible User Interface (TUI) for teaching ionic bonding to students of grade 8 to 10. ChemicAble acts as an exercise tool for students to understand better the concepts of ionic bonding by letting them explore and learn…."

Ionic bonding – an often mislearnt topic

This led to mixed feelings.

Anything that can support learners in making sense of the abstract, indeed intangible, nature of chemical bonding offered considerable potential to help learners and support teachers. Making the abstract more concrete is often a useful starting point in learning about theoretical concepts. So, this seemed a very well-motivated project that could really be useful.

It is sometimes argued that educational research is something of an irrelevance as it seldom impacts on classroom practice. In my (if, perhaps, biased) experienced, this is not so – but it is unrealistic to expect research to bring about widespread changes in educational practice quickly, and arguments that most teachers do not read research journals and so do not know who  initiated particular proposals has always seemed to me to be missing the point. We are not looking for teachers to pass tests on the content of research literature, and it is quite natural that the influence of research is usually indirect through, for example, informing teacher education and development programmes, or through revisions of curriculum, recommended teaching schemes, or formal standards.

This study by Agrawal and colleagues was not a theoretical treatise but a report of the implementation of a tool to support teaching and learning – the kind of thing that could directly impact teaching. So this was all promising.

However,I  also knew only too well that ionic bonding was a tricky topic. When I started research into learners' developing understanding of chemical bonding (three decades ago, now) I read several studies suggesting there were common alternative conceptions, that is misunderstandings, of ionic bonding found among students (e.g., Butts & Smith,  1987).

My own research suggested these were not just isolated notions, but often reflected a coherent alternative conceptual framework for ionic bonding that I labelled the 'molecular' framework (Taber, 1994, 1997). Research I have seen from other contexts since, leads me to believe this is an international phenomenon, and not limited to a specific curriculum context (Taber, 2013).

(Read about 'the Understanding Chemical Bonding project')

Ionic bonding – an often mistaught topic?

Indeed, I feel confident in suggesting:

  • secondary level students very commonly develop an alternative understanding of ionic bonding inconsistent with the scientific account…
  • …which they find difficult to move beyond should they continue to college level chemistry…
  • … and which they are convinced is what they were taught

Moreover, I strongly suspect that in quite a few cases, the alternative, incorrect model, is being taught. It is certainly presented, or at least implied, in a good many textbooks, and on a wide range of websites claiming to teach chemistry. I also suspect that in at least some cases,  teachers are teaching this, themselves thinking it is an acceptable approximation to the scientific account.

(Read about 'The molecular framework for ionic bonding')

A curriculum model of ionic bonding

So, I scanned the paper to see what account of the science was used as the basis for planning this teaching tool. I found this parenthetical account:

"{As stated in the NCERT book on Science for class X, chapter 3, 4, the electrons present in the outermost shell of an atom are known as the valence electrons. The outermost shell of an atom can accommodate a maximum of 8 electrons. Atoms of elements, having a completely filled outermost shell show little chemical activity. Of these inert elements, the helium atom has two electrons in its outermost shell and all other elements have atoms with eight electrons in the outermost shell.

The combining capacity of the atoms of other elements is explained as an attempt to attain a fully-filled outermost shell (8 electrons forming an octet). The number of electrons gained, lost or shared so as to make the octet of electrons in the outermost shell, gives us directly the combining capacity of the element called the valency. An ion is a charged particle and can be negatively or positively charged. A negatively charged ion is called an 'anion' and the positively charged ion, a 'cation'. Metals generally form cations and non-metals generally form anions. Atoms have tendency to complete their octet by this give and take of electron forming compounds. Compounds that are formed by electron transfer from metals to non-metals are called ionic compounds.}"

Agrawal et al., 2013 (no page numbers)

There are quite a few ideas here, and quite a lot of his account is perfectly canonical, at least at the level of description suitable for secondary school, introductory, chemistry. However, sprinkled in are some misleading statements.

So,

Curriculum statement Commentary
"…the electrons present in the outermost shell of an atom are known as the valence electrons."

 Fine

"The outermost shell of an atom can accommodate a maximum of 8 electrons."

This is only correct for period 2.

It is false false for period 1 (2 electrons), period 3 (18 electrons), period 4 (32 electrons), etcetera.

"Atoms of elements, having a completely filled outermost shell show little chemical activity. Of these inert elements, the helium atom has two electrons in its outermost shell and all other elements have atoms with eight electrons in the outermost shell."

Fine – apart from the reference to  "completely filled outermost shell"

Of the noble gases, only helium and neon have full outer shells.

'Atoms' of the heavier noble gases with full outer shells would not atoms, but ions, and these would be extremely unstable – i.e., they could not exist except hypothetically under extreme conditions of very intense electrical fields.

"The combining capacity of the atoms of other elements is explained as an attempt to attain a fully-filled outermost shell (8 electrons forming an octet). The number of electrons gained, lost or shared so as to make the octet of electrons in the outermost shell, gives us directly the combining capacity of the element called the valency."

Hm –  generally the valency can be identified with the difference between an atom's electronic configuration and the 'nearest' noble gas electronic configuration – which would be an octet of valence shell electrons, except in period one.

However,  the equivalence suggested here "a fully-filled outermost shell (8 electrons forming an octet)" is only true for period 2. An octet does not suffice for a full outer shell in period 3 (full at 18  electrons), or in period 4 (full at 32 electrons), etcetera.

And, in the statement, valency is described as being related to the intentions of atoms: "is explained as an attempt to attain…" (and "…electrons gained, lost or shared so as to…") which encourages student misconceptions. [Read about 'Learners' anthropomorphic thinking'.]

"An ion is a charged particle and can be negatively or positively charged. A negatively charged ion is called an 'anion' and the positively charged ion, a 'cation'. Metals generally form cations and non-metals generally form anions." Fine.
"Atoms have tendency to complete their octet by this give and take of electron forming compounds."

This is a common notion, but actually suspect. Some elements have an electron affinity such that the atoms would tend to pick up an electron spontaneously.

However, for an element with a valency of -2, such as oxygen, once it has become a singly charged anion (O), it will not attract a second electron, so apart from the halogens, this is misleading. The negatively charged O ion will indeed spontaneously repel/be repelled by a (negatively charged) electron.

Metallic elements have ionisation enthalpies showing that energy has to be applied to strip electrons from them – they certainly do not have a "tendency to complete their octet by this giv[ing]" of electrons.

"Compounds that are formed by electron transfer from metals to non-metals are called ionic compounds."

This is not usually how ionic compounds are formed. Although it is possible in the lab. to use binary synthesis (e.g., burning sodium in chlorine – not for the faint-hearted), that is not how ionic compounds are prepared in industry, or how the NaCl in table salt formed naturally.

(And even when burning sodium in chlorine, neither of the reactants are atomic, so even here there is no simple transfer of electrons between atoms.)

So this account is a mixture of the generally correct; the potentially misleading; and the downright wrong.

Agrawal and colleagues describe an ingenuous apparatus they had put together so that students can physically manipulate tokens to see ionic bond formation represented. This looks like something that younger secondary children would really enjoy.

They also report a small-scale informal evaluation of a classroom test of the apparatus with an unspecified number of students, reporting very positive responses. The children generally found the apparatus easy to use, the information it represented easy to understand, and they thought it helped them learn about chemical [ionic] compound formation.  So this seems very successful.

However, what did it help them learn?

The teaching model

"For example, when a token representing [a] sodium atom is placed on the table top, its valence shell (outermost shell) with 1 revolving valence electron is displayed around the token. When the student places a chlorine atom on the table, its valence shell along with 7 revolving valence electrons is displayed. The electron from the sodium atom gets transferred to the chlorine atom. +1 charge appears on the sodium atom due to loss of electron and -1 charge appears on the chlorine atom due to gain of electron. Both form a stable compound. The top bar on the user interface turns green to show success and displays the name of the stable compound so formed (sodium chloride, in this case). The valence shell of the atoms also turns green to show a stable compound."

Agrawal et al., 2013 (no page numbers)

Which sounds impressive, except NaCl is not formed by electron transfer, and with the ChemicAble the resulting structure is a single Na+-Cl ion pair, which does not represent the structure of the NaCl compound, and indeed would not be a stable structure.

Does it matter if children are taught scientific fairy tales?

The innovation likely motivated learners. And the authors seem to be basing their 'ChemicAble' on the curriculum models set out in the model science books produced by the Indian National Council of Educational Research and Training. So, the authors have produced something that helps children learn the science curriculum in that context,and so presumably what students will subsequently be examined on. Given that, it seems churlish to point out that what is being taught is scientifically wrong.

So, I find it hard to be critical of the authors, but I do wonder why governments want children to learn scientific fairy tales that are nonsense. The electron transfer model of ionic bonding seems to be popular with teachers, and received well by learners, so if the aim of education is to find material to teach that we can then test children on (so they can be graded, rated, sequences, selected), what is the problem? After all, I am a strong advocate for the idea that what we teach in school science is usually, necessarily, a simplification of the science – and indeed is basically a set of models – and not some absolute account of the universe.

Here the children, the teacher and the researchers have all put a lot of effort into helping learners acquire a scientifically incorrect account of ionic bonding. We think children should learn about the world at the molecular, naometre scale as this is such an important part of chemistry as a science. Yet, to my mind, if we are going to ask children to put time and effort into learning abstract models of the structure of nature at submicroscopic levels, even though we know this is challenging for them, then, although we need to work with simplified models, these should at least be intellectually honest models, and not accounts that we know are completely inauthentic and do not reflect the science. This is why I have been so critical of the incoherence and errors in the chemistry in the English National Curriculum (Taber, 2020).

Otherwise, education is reduced to a game for its own sake, and we may as well ask students to learn random Latin texts, or the plots of Grimms' Fairy Tales, or even the chemical procedures obscured by disguised reagents and allegorical language in alchemical texts, and then test them on how much they retain.

Actually, no, this learning of false models is worse than that, because learning these incorrect accounts confuses students and impedes their learning of the canonical scientific models if they later go on to study the subject further. So, if it is important that children learn something about ionic bonding, let's teaching something that is scientifically authentic and stop offering fairly tales about atoms wanting to fill their shells.

Sources cited:
 
 

 

In ionic bonding, they both want to get full outer shells

Keith S. Taber

Mohammed was a participant in the Understanding Science Project. When interviewed in the first term of his upper secondary (GCSE) science course (in Y10), he told me he had been learning about ionic bonding in one of his science classes. Mohammed had quite a clear idea about ionic bonding, which he described in terms of the interactions of two atoms:

And you said in chemistry you've been doing about electron arrangements [electronic configurations], and ionic bonding.

Yeah.

So what's ionic bonding, then?

Ionic bonding is when, like let's say, a sodium atom and take a chlorine atom, which make salt if they react. What happens is – the sodium atom has one electron on its outer shell, and the chlorine atom has seven, now they both want to get full outer shells, so if I er let's say move the electron from the sodium to the chlorine, then the chlorine would have a full outer shell because it would have eight, and because it's lost that shell the sodium will also have eight.

This account of ionic bonding is a common one, although it is inconsistent with the scientific model. A key problem here is that the driving force for bond formation is seen in terms of atoms wanting to complete their electron shells (the 'full shells explanatory principle'). Mohammed's explanation here uses anthropomorphism, as it treats the individual atoms as though they are alive and sentient, acting to meet their own needs – "they both want to get full outer shells".

When Mohammed was probed, he related a full outer shell to atomic stability (a central feature of the full shells explanatory principle).

Okay. How do you know they want full outer shells?

Because it makes them more stable.

Why does it make them more stable?

(pause, c.1 s)

Erm. (Why do electrons?*) (* sotto voce – apparently said to himself)

(pause, c.2s)

Er, because they don't react as much with other elements if they have a full outer shell.

I see.

They don't react.

There is an interesting contrast here between Mohammed's instant response that full shells "makes them more stable", and the long pause as he thought about why this might be so.

His response reflects something quite common in students' explanations n that a student asked why X is the case may respond by explaining why they think X is the case. (That is, as if an appropriate answer to the question "why is it raining so heavily?" would be "because I got soaked through getting here", i.e. actually responding to the question "how do you know that it is raining heavily?")

Such responses seem to be logically flawed, but of course may be a mis-perception of the question being asked (so the learner is answering the question they thought was asked), or (possibly the case here) substituting a response to a related question as a strategy adopted when aware that one cannot provide a satisfactory response to the actual question posed.

The anthropomorphic aspect of his earlier answer was probed:

How do the atoms know that they need to get a full outer shell, they want to get a full outer shell? Do they know about this stability thing?

Not really.

No?

It's just what happens.

Oh, I see, it's just what happens?

Yeah.

So although Mohammed used an anthropomorphic explanation, it seemed he did not mean this literally. (It may seem strange to suggest a 14 year old might consider atoms alive and sentient, but research suggests this is sometimes so!) This has been described as weak anthropomorphism, where the anthropomorphism is only used as a figure of speech. However, such language can act as a grounded learning impediment because if it becomes habitual it can stand in place of a scientific explanation (thus giving no reason to seek a canonical scientific understanding).

I went on to ask Mohammed about the formation of salt in the process he had described.

She'd never thought about whether ionic bonding is the same thing as chemical bonding

Keith S. Taber

Amy was a participant in the Understanding Science Project. When I talked to her near the start of her GCSE 'triple science' course in Y10 she told me that ionic bonding was "atoms which have either lost or gained electrons so they are either positively or negatively charged" and that chemical bonding was "like in a compound, where two or more elements are joined together", but she seemed unsure how the two concepts were related.

I followed up on Amy's use of the term 'compound' to explore how she understood the term:

How would you define a compound?

Erm Something which has erm two or more elements chemically bonded.

… So you give me an example of that, compound?

Erm, sodium oxide.

Sodium oxide, okay, so there are two or more elements chemically bonded in sodium oxide are there?

Uh hm

And what would those two or more elements be?

Sodium and oxygen.

Okay. Erm, so when we say sodium oxide is chemically bonded, what we are saying there is?

[pause, c 2s]

Erm – a sodium atom has been bonded with a oxygen atom to form erm a new substance.

So Amy's example of a compound was sodium oxide, which would normally be considered essentially an ionic compound, that is a compound with ionic bonding. So this gave me an opportunity to test out whether Amy saw the bonding in sodium chloride and sodium oxide as similar.


Okay, so that was chemical bonding,

Mm.

and that occurs with compounds?

Yeah.

And what did you say about ionic bonding?

Erm, it's the outer electrons they are transferred from one element to another.

Now what does that occur in? You gave me one example, didn't you?

Uh huh

Sodium chloride?

Yeah

Erm. Would sodium chloride be er an element?

[pause, c.2s]

Sodium chloride, no.

No?

It would be a compound.

You think that would be a compound?

Yeah.

And a compound is two or more elements joined together by chemical bonding?

Yeah.

So Amy had told me that sodium chloride, which had ionic bonding, was (like sodium oxide) a compound, and she had already told me that a compound comprised of "two or more elements chemically bonded", so it should be follow that sodium chloride (which had ionic bonding) had chemical bonding.

Do you think sodium chloride has chemical bonding?

Er – I think so

And it also has ionic bonding, or is that the same thing?

Erm,

[pause, c.2s]

I dunno, I've never thought about it that way, erm,

[pause c.3s]

I'm not sure, erm

[pause, c.2s]

I dunno, it might be.

Clearly, whatever Amy had been taught (and interviewing students reveals they often only recall partial and distorted versions of what was presented in class) she had learnt

  • (1) that ionic bonding was transfer of electrons (an alternative conception) as in the example of sodium transferring an electron to chlorine; and that
  • (2) a compounds was where two or more elements chemically bonded together, and an example was sodium oxide where the elements sodium and oxygen were chemical bonded.

Yet these two pieces of learning seemed to have been acquired as isolated ideas without any attempt to link them. Initially Amy seemed to feel ionic bonding and chemical bonding were quite separate concepts.

When taken through an argument that led to her telling me that sodium chloride, that she thought had ionic bonding, was a compound, which therefore had chemical bonding, there should have been a logical imperative to see that ionic bonding was chemical bonding (actually, a kind of chemical bonding – as the logic did not imply that chemical bonding was necessarily ionic bonding). Despite the implied syllogism:

  • sodium chloride has ionic bonding
  • sodium chloride is a compound
  • compounds have elements chemically bonded together
  • therefore ionic bonding …

Amy was unsure what to deduce, presumably because she had seen the two concepts of ionic bonding and chemical bonding as discrete notions and had had given no thought to a possible relationship between them. However explicit teaching had been on this point, it is very likely that the teacher had expected students to appreciate that ionic bonding was a type of chemical bonding – but Amy had not integrated these ideas into a connected conceptual structure (i.e., there was a learning bug that could be called a fragmentation learning impediment).

Ionic bonding – where the electron's transferred to complete the outer shell

Keith S. Taber

Amy was a participant in the Understanding Science Project. The first time I talked to Amy, near the start of her GCSE 'triple science' course in Y10 she told me that "in normal chemistry (i.e., the chemistry part of 'double science', as opposed to the optional additional chemistry lesson as part of 'triple science' that Amy also attended) we're doing about ionic bondingwhich was "atoms which have either lost or gained electrons so they are either positively or negatively charged" and

"how the outer electron's transferred…to complete the outer shell of the erm chlorine, thing, ion…and the sodium atom loses erm, one electron is it, yeah one electron, erm, which the chlorine atom gains, and that yeah that completes its outer shell and makes the sodium positively charged and the chlorine negatively charged".

Amy told me that "in ionic bonding it's the electrons that are transferred, I think."

So Amy had acquired a common alternative conception, i.e. that ionic bonding involved electron transfer, and that this occurs to atoms to complete their electron shells.

Ionic bonding refers to the forces between ions that hold the structure of an ionic substance together, rather than a mechanism by which such ions might hypothetically be formed – yet often learners come away form learning about ionic bonding identifying it with a process of electron transfer between atoms instead of interactions between ions which can be used to explain the properties of ionic substances.

Moreover, the hypothetical electron transfer is a fiction. In the case of NaCl such an electron transfer between isolated Na and Cl atoms would be energetically unfavourable, even if reactants containing discrete atoms were available (which is unrealistic).

Whether students are taught that ionic bonding is electron transfer is a moot point, but often introductory teaching of the topic focuses not on the nature of the bonding, but on presenting a (flawed) teaching model of how the ions in the ionic structure could form by electron transfer between atoms. As this mechanism is non-viable, and so not an authentic scientific account, it may seem odd that teachers commonly offer it.

One explanation may simply be custom or tradition has made this an insidious alternative conception. Science teachers and textbooks have 'always' offered the image of electron transfer as representing ionic bonding. So, this is what new teachers had themselves been taught at school, is what they often see in textbooks, and so what they learn to teach.

Another possible explanation is in terms of what what is known as the atomic ontology. This is the idea that the starting pint for thinking about chemistry at the submicroscopic level is atoms. Atoms do not need to be explained (as if in nature matter always starts as atoms – which is not the case) and other entities such as ions and molecules do need to be explained in terms of atoms. So, the atomic ontology is a kind of misleading alternative conceptual framework for thinking about chemistry at the submicroscopic level.

Sodium has one extra electron in its outer shell, and chlorine is minus an electron, so by force pulls they would hold together

Keith S. Taber

Annie was a participant in the Understanding Chemical Bonding project. She was interviewed near the start of her college 'A level' course (equivalent to Y12 of the English school system). Annie was shown, and asked about, a sequence of images representing atoms, molecules and other sub-microscopic structures of the kinds commonly used in chemistry teaching.

Focal figure (Fig. 5) presented to Annie

She was shown a representation of part of a lattice of ions in sodium chloride (see: Sodium and chlorine don't actually overlap or anything), but Annie identified the signified as atoms, not ions, because Annie had an idiosyncratic understanding of what was meant by charge. (Read: Na+ has an extra electron in its outer shell and Cl- is minus an electron and K-plus represents a potassium atom that has an extra electron.)

Annie was asked whether the structure made up of sodium and chlorine 'atoms' would hold together:

Do you think this thing would fall apart? Or would it hold together?

(pause, c.9s)

If you heated it, or reacted it in some way, it would hold together, and it would probably get held together by just forces.

By forces. Any idea what kind of forces would hold it together?

Probably just the attraction.

Uh hm?

The attraction from the plus to the minus because like chlorine's minus an electron and sodium is over an electron. So they could just like hold them together, but not actually combine.

Right, chlorine's, so sodium's, say that about the electrons again.

Sodium has like one extra electron, 'cause it has like an extra electron in its outer shell, and chlorine has seven electrons in its outer shell so its minus an electron so by sort of exchanging, the sodium combining with the chlorine just by force pulls they would hold together.

So Annie saw the plus (+) symbol to mean one electron over a full shell (2.8.1), and the minus (-) symbol to mean one electron short of an octet of electrons (2.8.7). For Annie these charges were not net electrical charges, but deviations from octet configurations. Yet, these 'deviation charges', for Annie, provided the basis for the attraction between the 'charged' atoms.

This was checked by asking Annie about the electron configurations.

So we looked at a sodium atom earlier, you recognised it as being a sodium atom, …

Can you tell me what the configuration is in terms of shells? How many in the first shell, how many in the second shell…

2.8.1

2.8.1?

Yeah.

So this here (indicating a cation on the figure), you are saying that this here is 2.8.1

Yes.

And this is 2.8.7 would it be?

Yeah, 2.8.7

And that is what holds them together the fact that this is one short,

yeah,

one over and one short.

One over, and that one's one short.

So the plus means one electron more than an outer, the full shell,

Yeah.

and the minus means one electron

Minus.

less than an outer shell,

Yeah.

and that's what holds them together.

Yeah.

Okay, so there is something holding them together,

right,

and it's to do with these pluses and these minuses,

Yes.

but what we don't have there is chemical bonding like we had before.

No.

Annie held an alternative conception of the nature of the charges associated with ions: that neutral atoms had 'charges' if they did not have full shells/octets of electrons. Whilst Annie's specific deviation charge conception would seem to be rather unusual, alternative conceptions relating to the significance of full shells / octets of electrons seems to be very common among chemistry students. Although Annie's thinking was idiosyncratic it reflected the common full shells explanatory principle that sees electronic configuration as a cause for chemical processes.

So Annie considered that these 'deviation' charges could actually give rise to forces between atoms (see also The force of lack of electrons pulls two hydrogen atoms together*).

Annie did not see ions, but atoms. But she thought that after a reaction, there would be attractions, 'force pulls', holding the product together, but this would not amount to chemical bonding.

Annie's notion of 'charges' on atoms (being extra or missing electrons in the outer shell), that led to her not recognising bonding in the NaCl, was an uncommon alternative conception notion. However, her notion that chemical bonding was something other than 'just forces', and that sometimes structures were held together by 'just forces' when there was no bonding, is a common alternative conception. Indeed it is part of a common 'molecular framework' for conceptualising ionic bonding, that is in turn a part of a common alternative conceptual framework for thinking about chemical bonding, stability and reactions: the octet framework.


Calcium and oxygen would not need to bond, they would just combine…

Calcium and oxygen would not need to bond, they would just combine, joining on to make up full shells

Keith S. Taber 

Annie was a participant in the Understanding Chemical Bonding project. She was interviewed near the start of her college 'A level' course (equivalent to Y12 of the English school system). Annie was shown, and asked about, a sequence of images representing atoms, molecules and other sub-microscopic structures of the kinds commonly used in chemistry teaching. Near the end of the interview, she was asked some general questions to recap on points she had made earlier. She suggested that Ca2+ and O2- would combine, but without any chemical bonding.

Could you have a double ionic bond?

(pause, c.3s)

Can you have a double bond that's ionic?

Not really sure.

If you had say, say you had calcium, two-plus (Ca2+), and oxygen two-minus (O2-),

yeah,

could that form a double bond?

(pause, c.4s)

Are you not sure?

It wouldn't need to.

It wouldn't need to?

No.

Why's that?

Because one's lacking two electrons, and one's got two, so, they would just combine without needing to sort of worry about other, other erm elements.

Right so they…

Sort of joining on to make up full shells.

So they combine, but you wouldn't call that a chemical bond?

No.

From what Annie had reported earlier in the interview, she would see Ca2+ as a calcium atom (that's "got two" electrons in its outer shell) and O2- as a oxygen atom (that was "lacking two electrons"), as she held an alternative conception of what was meant by the symbols used to indicate electrical charge plus and minus signs represent the charges on atoms)*.

Annie here suggests that the atoms with their charges (i.e., for Annie, deviations form full shells) would combine, and join up to obtain a full shell. From her perspective, there was no need for ionic bonding. Although Annie's notion of what was signified by the charge symbols would seem to be idiosyncratic, the idea that chemical processes occur to allow atoms to obtain full shells (the 'full shells explanatory principle') is one of the most common alternative conceptions in chemistry.