Scott Hutchinson
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<Right Step Periodic Table (RSPT) - response overview v3.pdf>Mark Leachmeta-synthesis
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The s-block is commonly shown split into two on defensible physical and chemical grounds. Moreover, its 1:11 separation and the d-block’s 1:9 separation are in a comparable range of unevenness. Further, the split of the d-block is likewise based on physical and chemical grounds.
Whereas the "irregularity" of the split s-block is regularly seen, the split d-block is well hidden given the 32-column format is rarely used, owing to its inconvenient size and limited practicality for wall charts, textbooks, or teaching. In the much more common 18-column medium form, the f-block is footnoted, the d-block appears contiguous, and the visual objections largely disappear.
On Aug 12, 2025, at 7:28 AM, Mark Leach <ma...@meta-synthesis.com> wrote:
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<Right Step Periodic Table (RSPT) - response overview v3.pdf>Mark Leachmeta-synthesis
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<Right Step Periodic Table (RSPT) - response overview v4.pdf>
On Aug 14, 2025, at 2:00 PM, Scott Hutcheon <scotth...@gmail.com> wrote:
Shared valence electron configurations
Recognisable chemical behaviour trends
This is a step away from the core achievement of the conventional PT: grouping elements vertically by their recurring chemical properties. It risks confusing learners who have just internalised these trends.
Scerri E 2004, The placement of hydrogen in the periodic table, Chemistry International, vol. 26, no. 3, https://publications.iupac.org/ci/2004/2603/ud2_scerri.html
Electronic structure: d-block vs f-block behaviour is largely distinct.
Chemistry: oxidation state ranges, coordination tendencies, and ionic radii behaviour diverge significantly.
History and usage: f-block chemistry is typically taught as a specialised topic, so its juxtaposition with mainstream transition metals seems arbitrary.
The result is that the "group" label risks becoming nominal only, without a coherent chemical identity.
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Regarding symmetry and asymmetry: we must always guard ourselves (a continuing point in the RSPT paper) between how the universe is and how we want it to be…
Scott
It seems we’re talking past each other a little. I don’t deny the reality of asymmetries—they’re crucial in physics and chemistry. My point is that symmetry and asymmetry coexist: laws often express symmetries, while their manifestations often break them in structured ways.
A periodic table that incorporates bilateral symmetry isn’t automatically a denial of asymmetry; it can be a visual way to highlight repeating regularities that do exist in quantum numbers, model-based electron configurations, and chemical trends. The question is not whether symmetry is “artificial” but whether the table illuminates or obscures the periodic law.
One of the simplest bilateral patterns in the periodic table is the relationship between metals and nonmetals. The distribution is certainly uneven, but the pairing is still evident—as are the parallels between the noble metals and noble gases, and between the alkali metals and halogen nonmetals. The RSPT, however, makes these bilateral relationships harder to discern, for example by placing the noble metals in two separate regions.
I’d also note that the conventional periodic table is designed to reflect the chemistry of elements under ambient to near-ambient conditions, which is why Li sits naturally over Na, and Be over Mg. While hydrogen’s cosmic abundance is important in astrophysics, it isn't the primary organising principle for a chemical table. The periodic law is about recurring physical and chemical properties, not cosmological proportions.
Hey René, appreciate the feedback,Yes, we're probably talking past each other (and it's probably on me). Totally agree with repeating quantum number, electron configuration, and chemical trend regularities and periodicities, would argue that they are not symmetrical in any way (per natural orbital filling chart versus theories) and that forcing them into artificial stacked blocks and/or bilateral symmetry form reduces their connection to universal reality in favour of local use (which I think you're arguing as a feature in the last two paragraphs)!As in the paper, have argued that forcing bilateral symmetry, as none actually exists, obscures relationships (example, when dropping the f-periods for the standard table) rather than clarify them.Had definitely considered how adversely working chemists would react to a periodic table based on elemental evolution and its discovered direct connection to sequential atomic numbers and physical periodic orbital filling (which is the fundamental reason for chemical properties, similarities, and periodicities), and had created the RSPT – Chemistry Lab variant in the first round of creation three years ago.
As the RSPT is based on basic physical reality, it was a simple solution, and the row spaces between H and the Halogens and He and the inert gases do visually indicate/reinforce just how physically different and chemically unrelated they are though:
<RSPT-36 - schwarz full colour -chemistry model.png>
However, per the paper, would again argue that placing simpler duplet s2 Helium over the much more complex octet p6 inert gases signals apophenia (https://en.wikipedia.org/wiki/Apophenia) or judicially choosing (cherry picking) data points, while ignoring counterpoints, to support a pet theory (that the duplet rule and 18-electron rule match the octet rule, which is what they were invented to do).While the octet rule continues to be widely taught, the duplet rule not so much for good reason, and the 18-electron rule has so many exceptions as to not even be a rule. Would also disagree with Hydrogen over the Halogens as another example of seek and ye shall find relationships.Had even created a version showing (like the updated capstone you shared) the RSPT – Chemistry Lab variant including the (correct here!) 0s or Period 0 pre- or proto-elements:
<RSPT-36 - schwarz full colour -chemistry model - 0s.png>Would these versions work better towards addressing your concerns for local human working chemists?
On Sat, Aug 16, 2025 at 6:39 PM Rene <re...@iinet.net.au> wrote:On 16 Aug 2025, at 07:46, Scott Hutcheon <scotth...@gmail.com> wrote:Regarding symmetry and asymmetry: we must always guard ourselves (a continuing point in the RSPT paper) between how the universe is and how we want it to be…Scott
It seems we’re talking past each other a little. I don’t deny the reality of asymmetries—they’re crucial in physics and chemistry. My point is that symmetry and asymmetry coexist: laws often express symmetries, while their manifestations often break them in structured ways.
A periodic table that incorporates bilateral symmetry isn’t automatically a denial of asymmetry; it can be a visual way to highlight repeating regularities that do exist in quantum numbers, model-based electron configurations, and chemical trends. The question is not whether symmetry is “artificial” but whether the table illuminates or obscures the periodic law.One of the simplest bilateral patterns in the periodic table is the relationship between metals and nonmetals. The distribution is certainly uneven, but the pairing is still evident—as are the parallels between the noble metals and noble gases, and between the alkali metals and halogen nonmetals. The RSPT, however, makes these bilateral relationships harder to discern, for example by placing the noble metals in two separate regions.
I’d also note that the conventional periodic table is designed to reflect the chemistry of elements under ambient to near-ambient conditions, which is why Li sits naturally over Na, and Be over Mg. While hydrogen’s cosmic abundance is important in astrophysics, it isn't the primary organising principle for a chemical table. The periodic law is about recurring physical and chemical properties, not cosmological proportions.René
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On Aug 17, 2025, at 8:49 PM, Scott Hutcheon <scotth...@gmail.com> wrote:Hi Jess,S-orbitals have a spherical shape: therefore they do not have lobes because the probability of finding the electron is the same in all directions from the nucleus.1s (2) → 2s (2) → 2p (6) → 3s (2) → 3p (6) → 4s (2) → 3d (10) → 4p (6) → 5s (2) → 4d (10) → 5p (6) → 6s (2) → 4f (14) → 5d (10) → 6p (6) → 7s (2) → 5f (14) → 6d (10) → 7p (6) →I honestly get that because each orbital period contains an even number of elements there is an incredible temptation to satisfy our very strong human desires to force bilateral symmetry. A great deal of creative work went into artificially organizing the current standard periodic table to appear nearly bilaterally symmetrical and balanced despite having an uneven 7 s-periods connected to an even 6 p-periods, an even 4 d-periods, and an even 2 f-periods.
However, exactly as you say, each orbitals fills "up" spin sequentially "left to right" before then filling "down" spin sequentially "left to right" per Pauli's exclusion (though why the left to right "up" spin first hasn't been adequately explained from first principles).
This means the only possible electronically symmetric elements in each orbital period are the end ones (even number of all up and all down spins filled). This is also why the symmetrically filled octet gases are so stable.Symmetric = stable is a good way of looking at it (so every atomic, and therefore electronic, even-numbered element is more stable up to the most stable fully symmetric ones at the end of each period). This is exactly why the periodic table cannot be symmetric -- as only the final elements in each period are electronically symmetrical. Which is only 19 elements out of the 118 (an uneven number due to the uneven 7 s-periods).This is why the "final" end even-numbered elements of 5d and 6d (only realized with the RSPT) are liquid at standard (unlike 3d and 4d which are not, which is a further reason they shouldn't be stacked together). It's also why period end even-numbered elements form gases at 1s2 and p6, why the Column of Instability is at uneven lobes 5, and why the column of anomalous configurations is at even lobes 8, etc.But a deeper, more comprehensive understanding than symmetry and even-numbered stability needs to be discovered to understand why the rest of the s2 elements aren't as stable on their own (or have unique shared characteristics like the p6 gases), why 1s1 Hydrogen is a gas, other related issues with the p-elements, and the same for the 3d and 4d and 4f and 5f period end even and symmetric elements.This symmetry related to even-numberedness also exists for the nuclei with magic and doubly magic symmetrically stable and even-numbered protons (and neutrons including for isotopes).
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Hello all,As the discussion seems to have gone away from the contents of the RSPT paper, let's reset and focus.Since the paper bypasses all current and previous well-worn and memorized judicial theoretical arguments by returning to the basic natural reality of physical and chemical orbital periods and their properties, similarities, and periodicities, it should be made clear here that it is obvious to anyone who has read the paper that responses instead coming from assumed understandings or preconceived notions about the RSPT or the paper will not hold up or even be relevant after reading the paper.
<Right Step Periodic Table (RSPT) - response overview v6.pdf>
Please respond to or raise issues with the attached v6 paper. For anyone who has read earlier versions, only the last few pages of Section 1 and Section 3 have been updated and expanded.
Gains: logical sequence, no footnotes, strict adherence to orbital order.
Losses: chemical coherence, pedagogical clarity, usability.
In short, the RSPT might make sense as a theoretical model of orbital filling, especially if you accept the “sloppy” version of the Aufbau principle popular in textbooks, but as a practical periodic table of chemistry my concerns stand: it undermines the very regularities that make the table useful.
![]() | |
On Aug 20, 2025, at 1:17 AM, Rene <re...@iinet.net.au> wrote:
On Aug 20, 2025, at 8:01 AM, Mario Rodriguez <mavo...@yahoo.es> wrote:
I wouldn’t be too harsh on the Aufbau principle. It can be ammended with 2 rules:1. Stability of half- and fully-filled d and f orbitals: d4 and d9 tend to capture 1e from the s orbital to achieve d5 (half-filled) and d10 (fully-filled). f8 expels 1e to the d orbital, resulting in f7 (half-filled). The only exception is wolfram, which follows the regular filling.2. f orbitals never begin filling. The first electron goes into a d orbital. This d1 persists for the first two lanthanides and the first five actinides, before this electron is reclaimed by the f orbital. The only exception is thorium, which is d2.Beyond these two rules (and their two exceptions), only palladium (which fills d10 before silver) and platinum remain as additional exceptions.Mario RP
Hi ReneThank you for citing the term“Sloppy aufbau” which I coined 13 years ago in an article in the UK journal Education in Chemistry
On Aug 20, 2025, at 9:42 AM, ERIC SCERRI <sce...@g.ucla.edu> wrote:
Eric Scerri----------------------------------------------------------------------------------------------------------
On Aug 20, 2025, at 7:59 AM, Mario Rodriguez <mavo...@yahoo.es> wrote:
I wouldn’t be too harsh on the Aufbau principle. It can be ammended with 2 rules:1. Stability of half- and fully-filled d and f orbitals: d4 and d9 tend to capture 1e from the s orbital to achieve d5 (half-filled) and d10 (fully-filled). f8 expels 1e to the d orbital, resulting in f7 (half-filled). The only exception is wolfram, which follows the regular filling.2. f orbitals never begin filling. The first electron goes into a d orbital. This d1 persists for the first two lanthanides and the first five actinides, before this electron is reclaimed by the f orbital. The only exception is thorium, which is d2.Beyond these two rules (and their two exceptions), only palladium (which fills d10 before silver) and platinum remain as additional exceptions.Mario RP
Hi ReneThank you for citing the term“Sloppy aufbau” which I coined 13 years ago in an article in the UK journal Education in Chemistry
<109409_p024_eic-aufbau_thumb.jpg>
On Aug 20, 2025, at 9:57 AM, Scott Hutcheon <scotth...@gmail.com> wrote:this discussion also devolving, there are no concerns as it was always expected that the first fully scientific table would trigger emotional responses: “All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident.” -- author unknown, paraphrased from Schopenhauer
As well, if the RSPT paper is guilty of anything, it's probably of being too stereotypically Canadian by adhering to the following advice: “Always remember that to argue is to try and break down the reality of the person you are arguing against. It is painful to lose or change even the smallest part of one's reality, so be kind, especially if you might be right.” – paraphrased from Haruki Murakami
On Aug 20, 2025, at 10:20 AM, Scott Hutcheon <scotth...@gmail.com> wrote:100% agree. The goal is always to eventually submit to a peer-reviewed journal where it can be falsified and verified (part of the reason for the success of science) -- and any assumption otherwise doesn't make sense.While I didn't originally submit the paper to this group, I'm grateful it was (and thankful for being accepted into the group) as the group discussion helps serve the function of a peer-reviewed preprint (though obviously better if the paper was read).
<Right Step Periodic Table (RSPT) - response overview v6.pdf>
On Aug 20, 2025, at 7:59 AM, Mario Rodriguez <mavo...@yahoo.es> wrote:
I wouldn’t be too harsh on the Aufbau principle. It can be ammended with 2 rules:1. Stability of half- and fully-filled d and f orbitals: d4 and d9 tend to capture 1e from the s orbital to achieve d5 (half-filled) and d10 (fully-filled). f8 expels 1e to the d orbital, resulting in f7 (half-filled). The only exception is wolfram, which follows the regular filling.2. f orbitals never begin filling. The first electron goes into a d orbital. This d1 persists for the first two lanthanides and the first five actinides, before this electron is reclaimed by the f orbital. The only exception is thorium, which is d2.Beyond these two rules (and their two exceptions), only palladium (which fills d10 before silver) and platinum remain as additional exceptions.Mario RP
Hi ReneThank you for citing the term“Sloppy aufbau” which I coined 13 years ago in an article in the UK journal Education in Chemistry
<109409_p024_eic-aufbau_thumb.jpg>
On Aug 20, 2025, at 12:07 PM, Mario Rodriguez <mavo...@yahoo.es> wrote:Dear Eric,Thank you for your prompt response. I am aware that the Aufbau principle has several exceptions, which is why I proposed refining it with two additional rules to minimize them. The question then becomes: what is the alternative? Should we abandon the Aufbau principle altogether and simply ask people to memorize the 118 electronic configurations? Or perhaps attempt to develop an entirely new predictive model for electronic configurations? and if so, what would those rules be?
We should keep in mind that many periodic properties also involve exceptions, and yet the periodic table (and all its variants) are accepted.
Regarding the f-block, I believe we agree that the combined rule, where f8 adjusts to f7 d1, along with the initial d1 for the first two lanthanides and five actinides, provides accurate predictions across this block, with the single exception of thorium (d2). Having only one exception in an entire block is, in fact, encouraging; and if someone can reconcile thorium, even better.It seems, then, that the real challenge lies in the d-block. To clarify, I will list the elements along with their actual configurations, the standard Aufbau prediction, and "my" proposed correction (where the rules are that d4 s2 → d5 s1 and d9 s2 → d10 s1).4 Sc Ti V Cr Mn Fe Co Ni Cu ZnReal: d1 s2 d2 s2 d3 s2 d5 s1 d5 s2 d6 s2 d7 s2 d8 s2 d10 s1 d10 s2Aufbau: d1 s2 d2 s2 d3 s2 d4 s2 d5 s2 d6 s2 d7 s2 d8 s2 d9 s2 d10 s2 2 Mismatches: Cr, CuCorrected: d1 s2 d2 s2 d3 s2 d5 s1 d5 s2 d6 s2 d7 s2 d8 s2 d10 s1 d10 s2 No mismatches5 Y Zr Nb Mo Tc Ru Rh Pd Ag CdReal: d1 s2 d2 s2 d4 s1 d5 s1 d5 s2 d7 s1 d8 s1 d10 s0 d10 s1 d10 s2Aufbau: d1 s2 d2 s2 d3 s2 d4 s2 d5 s2 d6 s2 d7 s2 d8 s2 d9 s2 d10 s2 6 Mismatches: Nb, Mo, Ru, Rh, Pd, AgCorrected: d1 s2 d2 s2 d3 s2 d5 s1 d5 s2 d6 s2 d7 s2 d8 s2 d10 s1 d10 s2 4 Mismatches: Nb, Ru, Rh, Pd6 Lu Hf Ta W Re Os Ir Pt Au HgReal: d1 s2 d2 s2 d3 s2 d4 s2 d5 s2 d6 s2 d7 s2 d9 s1 d10 s1 d10 s2Aufbau: d1 s2 d2 s2 d3 s2 d4 s2 d5 s2 d6 s2 d7 s2 d8 s2 d9 s2 d10 s2 2 Mismatches: Pt, AuCorrected: d1 s2 d2 s2 d3 s2 d5 s1 d5 s2 d6 s2 d7 s2 d8 s2 d10 s1 d10 s2 2 Mismatches: W, PtIn the d-block, the Aufbau principle produces 10 mismatches, while my proposed correction reduces this to 6. In other words, Aufbau succeeds in 20 out of 30 cases (66.6%), whereas my correction achieves 24 out of 30 (80%).Expanding the scope to the periodic table up to nobelium (102), the Aufbau principle correctly predicts 83 of 102 configurations (81.4%), while my correction accounts for 95 of 102 (93.1%).
EricP.S.Completely separate point. To base a periodic table on the fact that 3 particular radioactive elements align together is the height of folly in my view.The periodic table is primarily about chemical reactivity not radioactivity. Plus we certainly dont want to destroy well-known chemical periodicities at the expense of a single property such as radioactivity. Not that anybody here would ever dream of doing this of course. I’m just saying.
On Aug 20, 2025, at 1:37 PM, Scott Hutcheon <scotth...@gmail.com> wrote:Dare to dream!Per above unread discussions, Figures 7a, 7b, 7c, and 7d where electron affinity, electronegativity, ionization energy, atomic weight, and orbital-filling trends expect the corrected d- and f-period configurations.
Chemistry evolves from Physics, a scientific pt has to support both.
On Aug 20, 2025, at 2:13 PM, Mario Rodriguez <mavo...@yahoo.es> wrote:Hi Eric,Just answering few things regarding Aufbau,- Yes a paper carefully laying out this information could be useful especially in the educational context.REPLY: I take note. At the moment my life is going through some changes and I have very limited time to write, apart from long emails. Still, I’m keeping track to develop this further once things have settled.- I can accept that a full shell might be stable, as in the case of the noble gases but where is it written that half-filled shells confer stability? It’s not a principle of physics but just an ad hoc explanation which is given to beginning students.REPLY: In the d-block, this explains the transitions from d4 s2 to d5 s1 in chromium and molybdenum, and in the f-block, from f8 to f7 d1 in gadolinium and curium. Half-filled shells have all their orbitals occupied, though with one electron instead of the two found in fully filled shells. The only exception is wolfram. This phenomenon affects two elements in the d-block and two in the f-block, and I think it’s significant enough not to be dismissed.
On Aug 21, 2025, at 12:56 AM, Mario Rodriguez <mavo...@yahoo.es> wrote:Thank you for sharing this section of your paper. I had read it previously, and here are my thoughts on some specific points::- Does a half-filled sub-shell lead to an anomalous configuration, in the sense of having an outer shell of ns1?REPLY: These nomalous configurations don´t occur exclusively in the d block:d4 s2 → d5 s1: Cr, Mo (but not W)f8 → f7 d1: Gd, CmFor some reason, in the middle of these blocks, anomalies appear trying to reach the half-filled d or f subshells. d subshells prefer to take 1 electron from the s orbital, while the f subshells prefer to push one into the d orbital, I guess for having proximal energies.- The answer is no, since atoms such as manganese and technetium possess half-filled d sub-shells, yet they do not have outer shells consisting of ns1 configurations.REPLY: Mn and Tc already have configurations of d5 s2, so they do not need to pick or expel electrons to reach d5. The same applies to Zn to Hg, which already possess d10 s2 without requiring rearrangement. The elements that adjust to d10 by moving an electron are d9 s2 → d10 s1: Cu to Au.- Conversely, if a metal atom has an anomalous configuration, is this always accompanied by a half-filled sub-shell configuration?REPLY: The argument "half-filled subshells can´t explain all anomalies, then it can´t be the reason" is not valid as several reasons can explain anomalies. I proposed a Rule 1 “half- and fully-filled stability rule”, which explains 7 anomalies (4 involving half-filled, 3 involving fully filled), and a Rule 2 "in the f block, filling always begins with d1, which persists in the first 2 lanthanides and 5 actinides before being reclaimed by the f subshell". This trend explains 6 anomalies, with Th (d2) being the only exception. With these two rules combined, the number of anomalies can be reduced to 7.
- it is more accurate to say that this configuration occurs by default, since the other option represents a less stable arrangement of electrons.REPLY: That is always correct, though it is not a predictive rule. The key question remains why a given arrangement is more stable than the alternatives.Finally, regarding Sc, I must admit I am still not fully clear. If I understand correctly, the 4s orbital should be filled after 3d. But if we start filling 3d with 3 electrons, the configuration would be 3d3, leaving 4s unoccupied (since 3d can still hold 7 more). By contrast, if we begin with 4s, the configuration becomes 4s2 3d1, which is indeed the actual one. I openly acknowledge that I have not yet fully grasped this proposed modification to the Aufbau principle.
I always put “anomalous” in quotes because the electronic configurations are only anomalous with respect to an idealised Madelung’s rule, not with respect to nature itself.Or, as T.H. Huxley put it: "the great tragedy of Science is the slaying of a beautiful hypothesis by an ugly fact.”
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…valence electron configurations of atoms and ions are also important in predicting the periodicity of chemical properties. Since ions are more important than isolated gaseous atoms for nearly all atoms, and important ions have no anomalous electron configurations, there is little reason to worry students with anomalous electron configurations of atoms: we prefer to teach ‘characteristic’ electron configurations without anomalies in the occupancies of d- and s-orbitals in the transition elements or d-, s-, and f- orbitals in the inner transition elements.
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Scerri ER 2021, The Periodic Table: Its Story and Its Significance, 2d ed., Oxford University Press, New York
The rule is based on (1) consistency with the number of f-electrons in the trivalent cations of the 4f elements; (2) the Ln contraction starting at Ce and culminating at Lu i.e. from the start to the end of the f-block; and (3) each block starting with the appearance of the first applicable electron."The third member of Group 3 is La."
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On 26 Aug 2025, at 07:26, 'Mario Rodriguez' via Periodic table mailing list <PT...@googlegroups.com> wrote:Your point 3 “each block starting with the appearance of the first applicable electron” can be falsified with Lr itself.
Now, regarding point 1, "consistency with the number of f-electrons in the trivalent cations of the 4f elements; The series starts with Ce^3+ as [Xe]4f1 and concludes with Yb^3+ [Xe]4f13 and Lu^3+ [Xe]4f14".It is true that lanthanides most often appear in the +3 state, but we cannot ignore that Ce, Nd, and Tb can also reach +4, along with other less common valencies.
When we move to actinides, we have a big problem as trivalent cations are not common:
Chapter 2 “the debate on group 3” (Neve, F.: Chemistry of superheavy transition metals. J. Coord. Chem. 7(17–18), 2287–2307 (2022)):
Chapter “Lutetium or lanthanum above yttrium” (Winter, M.J.: Chemdex: Quantification and distributions of valence numbers, oxidation numbers, coordination numbers, electron numbers, and covalent bond classes for the elements. Dalton Trans. 53, 493–511 (2024)):“The trends for the corresponding average CN values of groups 4–7 elements are reminiscent of the Sc–Y–Lu trend and on that basis Lu is better placed beneath Y rather than La in a chemical periodic table based upon VN and CN.”
"Strub, E., et al.: Pertechnetates– A Structural Study Across the Periodic Table. Chem. Eur. J. 30, e202400131(2024)"Finally, the bond lengths of perrhenates and pertechnetates of Sc, Y, La and Lu shall be compared (Figure 30).
It also reflects that bond lengths as well as crystal radii of the Lu and Y compounds are very similar, as would be expected for any 4d/5d element pair. In this sense, our data might be a humble contribution to the ongoing discussion as to whether La or Lu (and Ac or Lr, respectively) should be placed beneath Sc and Y in the periodic table. Considering our data, we widely agree with the view of:[69–71]
"From the early transition metals, Sc and Y serve as lighter homologues for lanthanoid elements, in particular the heavier lanthanoids. They support the placement of Lu in the periodic table underneath Y"
And finally, I think that the ugliness of splitting the d-block (as Eric remarked) outweighs the appeal of the numerology of La based on its Z :)
I also enjoy these exchanges, even if my messages tend to be quite long!Mario RP
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"What we're interested in is what Nature is like, not how easy it is to draw it."Yet, organizing is a part of human nature. Seeing nature as it is, without our natural ability to idealize would make our heads explode.
[i] Richard Feynman, in Bent H 2006, New Ideas in Chemistry from Fresh Energy for the Periodic Law. Author-House, Bloomington, Indiana, p. 140
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Larry.
Regrettably, IUPAC did not accept the recommendation that my working group and I made concerning group 3.This was published in the IUPAC magazine “Chemistry International”. I believe I may have posted it a while ago, but here it is again,RegardsEric Scerri
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<S. Alvarez.pdf>
On 31 Aug 2025, at 14:47, ERIC SCERRI <sce...@g.ucla.edu> wrote:
Dear Jess,Many thanks for posting the article by Santiago Alvarez, whom I know. But I was not aware of this article, which fully supportsmy contention that Lu and Lr should be placed in group 3 rather than La and Ac.
On Aug 30, 2025, at 6:38 PM, Larry T. <ora...@gmail.com> wrote: