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How about discussing navigation aids? The present one, seen on the information box for every element (look at Neon for example) is arguably too wide for easy use. It has 32 columns and as a result provides only tiny boxes for people to use to link to other elements that they may wish to jump to next. I'd like to make a proposal for a new navigation aid of 18 columns, as below. Astute readers will realise that this also has something to do with the debate we have recently been having on this page!
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Michael D. Turnbull (talk) 09:49, 21 July 2020 (UTC)
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Michael D. Turnbull (talk) 10:42, 21 July 2020 (UTC)
Ah, now we are getting somewhere! What we were all forgetting is that a wiki page is not the same as a printed page. We have the luxury of being able to link cells in the navigation table to anything we like AND give a hover-over message that's appropriate. This is very useful when filling in the contentious cells that IUPAC places asterisks in. We can do better..... see my third and final suggestion below. For the avoidance of doubt, I've added back the usual table legend at the bottom and, yes, I would add a blank row between the main body and the Lanthanide/Actinide strip, if only I could work out how to do so. Note what happens when you click on the cells now below element Y: it's not the same as the click on the words "Lanthanides" or "Actinides" at lower left.
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I don't think we need any more full versions to discuss the issue and find a consensus for this navigation table to replace ((Compact periodic table))
. We just need to agree a) the colours - I see no need to change; b) the short text where I've currently got La em-dash Lu; c) the Hover-text (I think this has to be the page name that the click will link to) and d) the correct wikilink-on-click Michael D. Turnbull (talk) 09:16, 22 July 2020 (UTC)
“ | The technique employed was claimed to distinguish between Group 3 elements (lanthanides and actinides) and combined Groups 4 and 5. ... No carrier-free actinide tracers were employed despite the extremely complex oxidation chemistry and adsorption quirks of those Group 3 elements in contrast to lanthanide behavior. | ” |
— That JWP report |
((periodic table))
is, however, enormous and I hesitated to inflict it on this thread. You may not be aware that the template used in the infoboxes at each element page is very much based on what we're discussing here, which as you know goes at the foot of each article. It gets some clever tweaks that highlight the element in question in the periodic table when used in the infobox. So, once we have settled the current discussion and found a competent volunteer who is familiar with template documentation and won't mess up the implementations (that ain't me!) all relevant en.wiki templates should be done. If you feel a separate discussion is needed for ((periodic table))
, please start one, or sandbox ideas to link here (the template has its own sandbox for that purpose). Michael D. Turnbull (talk) 15:13, 22 July 2020 (UTC)There are several things to consider here. [start of comment by Sandbh 23:42, 23 July 2020 (UTC)]
1. There is no such thing as an IUPAC recommended or endorsed periodic table. The table that appears on their website is used within IUAPC. A spokesperson has made it clear that IUPAC does not recommended or endorse any form of periodic table (Leigh 2009).
2. The IUPAC table is now especially "bad" since they deliberately misaligned the 15-element wide f-block purely so that they could fit the IUPAC logo in.
3. The 18-column *-** form results in the f-block becoming part of the d-block. This is so bad that Jensen (2008) referred to it "chemical nonsense" and that, "IUPAC or not, I can hardly believe that a modern inorganic chemist would advocate such an antiquated interpretation of these elements, unless, as noted above, they have lost all contact between the underlying premises of their periodic table and the facts of chemistry." Disclaimer: While I agree with Jensen in this case, I disagree with his position on Group 3.
4. Using the *-** form is not consistent with the literature. Thus, Mathias (1969) grumbled about La in group 3 being the most popular form. Myers, Oldham and Tocci (2004, p. 130) found La and Ac to be the most popular form of periodic table, a sentiment echoed by Clarke and White (2008); and Lavelle (2008; 2009).
5. A survey by the IUPAC Group 3 project team found that the majority of textbook and other periodic tables in the 18-column format show the elements of group 3 as scandium, yttrium, lanthanum and actinium. The survey did not include a Google image search, since such results are plagued by bias arising from the false impression that the IUPAC *-** table is “official”, and unreliable sources.
6. As R8R noted, "consistency with literature is of the uttermost importance for Wikipedia if literature itself shows such a consistency; Wikipedia is meant to be a tertiary source."
--- Sandbh (talk) 01:19, 23 July 2020 (UTC)
((periodic table))
, which doesn't. I have been WP:BOLD and made these changes now, so everyone can see their effect. Incidentally, the IUPAC website today says "The question of precisely which elements should be placed in group 3 has been debated from time to time. An IUPAC project has been recently initiated to resolve the question. Will group 3 consist of Sc, Y, Lu, and Lr or, will it consist of Sc, Y, La and Ac? (My emphasis)" Michael D. Turnbull (talk) 14:37, 23 July 2020 (UTC)versions 1 and 2 are now superceded by version 3, which is all we need to discuss beyond this point.No. "Superceded" has not been established. Thi subthread, with its non-sequitir ignation, is invalid. Dead on arrival. No need to spend time on this. -DePiep (talk) 23:47, 23 July 2020 (UTC)
I make the following observations: The spread is 4:1:1, where Sc-Y-La-Ac is four times as common as either *-** or Lu-Lr. This is nowhere near any degree of ambiguity sufficient to justify a judgement call or compromise. Going for Sc-Y-La does not pick a side. There is no finely balanced contest of sides.
The misalignment of the IUPAC table is an issue in that it prioritises vanity branding over the alignment of the early Ln and An with their 5d analogies. Yes, the perception of such "stupidity" is circulating within the chemistry community.
Nobody takes account of the strong resistance IUPAC has to making recommendations on group composition or the form of periodic table. For example, if the IUPAC recommends group 3 as La will this render the Janet table as being politically incorrect or wrong-headed thinking? No doubt the IUPAC would have to set up re-education internment camps for Lu supporters. Next to be labelled as deviant will be Group 14 in the Earth Scientist’s periodic table being composed of carbon, silicon, titanium, zirconium, and hafnium rather than the standard set of carbon, silicon, germanium, tin, and lead. Book burnings to follow.
Once the Group 3 project has made its report there is no guarantee the IUPAC will accept it. If it is released it will go to the chemistry community for consultation. Even then there is no guarantee the IUPAC will turn the report into a recommendation.
La or Lu, plus La-Lr breaches the maxim of one element one place.
The place for accommodating the variants of Group 3 is in the main body of our periodic table article, as we do now. Here we write that, "Although scandium and yttrium are always the first two elements in group 3, the identity of the next two elements is not completely settled. They are commonly lanthanum and actinium [by a wide margin], and [significantly] less often lutetium and lawrencium." (my brackets)
Just so. --- Sandbh (talk) 00:24, 24 July 2020 (UTC)
Decade | La under Y | Lu under Y | * under Y | Total |
---|---|---|---|---|
1970s | 18 69% |
2 8% |
6 23% |
26 |
1980s | 31 78% |
6 15% |
3 8% |
40 |
1990s | 27 82% |
2 6% |
4 12% |
33 |
2000s | 38 62% |
14 23% |
9 15% |
61 |
2010s | 16 48% |
6 18% |
11 33% |
33 |
@Double sharp: Why are you engaging in WP:FORUMSHOPing? You have posted the same content to our project page. Please confine your argument to one forum. And where is the hyperbolic language coming from? It is like there are two of you: one who is calm; the other one who is foaming at the mouth. Sandbh (talk) 06:48, 24 July 2020 (UTC)
Do not use techniques that require interaction to provide information, such as tooltips or any other "hover" text. [((abbr)) is the exception]See for example issues with title: not available in mobile devices, not working well with screen readers. The information better be provided in a textual footnote.
((periodic table))
and new live 18-column navbox. I am happy to agree with your technical views on the implementation for the element Infoboxes and give up on the other ideas as being unworkable, bad practice, or impossible to gain consensus. There is no need to present two group 3 forms and I'm happy to stick with Wikipedia's current implementation: I believe that even ^_^ accepts this for now. Michael D. Turnbull (talk) 11:22, 25 July 2020 (UTC)
(ec) I have made these edits boldly:
arguably too wide for easy use, esp on smaller screens: I have reformed the format into an equivalent 18-column Periodic table.
Astute readers will realise that this also has something to do with the debate we have recently been having on this page!. But exactly the opposite is at hand: the group 3 discussion (both at enwiki and in RL) is not related to the form being 18- or 32-column. For illustration: RFC initator Double sharp has presented, correctly and gently, each of the three options in both their 18- and 32-column form, i.e., six PTs in total.
I have reverted this change in ((Periodic table (navbox))) [2], as some editors pointed to a misunderstanding and confusion in this thread. The navbox is back to 32-column format. This does not state any prejudice. New proposals best be made in a new thread. See also #Propose closing as is below. -DePiep (talk) 09:47, 26 July 2020 (UTC)
@Michael D. Turnbull, DePiep, Sandbh, and Double sharp: sorry, I haven't been watching the discussion very closely. But did we arrive to the conclusion we wanted? I thought that if we needed to switch from 32 columns to 18 anywhere, it would be the small table in the infobox rather than the one at the bottom of a page. Do we not want to change it instead? Was there really a problem with the table at the bottom of our element articles?
Also, DePiep, on my screen the renewed table looks not only unpleasant (cells have become waay to wide, I can attach a screenshot if you want to look at it) but also strange because some columns differ by their width. Can this be helped?--R8R (talk) 18:21, 25 July 2020 (UTC)
@DePiep and R8R: I understood R8R and I were supporting an 18-column table at the top of the info-box, and retaining the 32-column table at the foot of each element article. That way the reader gains a sense of familiarity from the 18-column table, then has the "aha" moment at the foot of the page, which shows where the f-block fits into the 18-column table.
The way this proposal was initiated and managed (in good faith by everyone, no doubt) is a text-book example on how not to do it. Sandbh (talk) 07:58, 26 July 2020 (UTC)
@Michael D. Turnbull, Sandbh, Double sharp, and R8R:
![]() | This request for help from administrators has been answered. If you need more help or have additional questions, please reapply the ((admin help)) template, or contact the responding user(s) directly on their own user talk page. |
I request an uninvolved editor to close this thread #A_navigation_aid_for_Wikipedia,_based_on_the_periodic_table as "no consensus" or "procedural close". (per Wikipedia:Closing discussions: # further contributions are unlikely to be helpful). Contributors, including OP, have supported the conclusion that too many issues were discussed intertwined, thereby confusing the threads of argument. This #Propose closing as is invites to restart (from status quo ante, no prejudice) with a more crisp initial question/proposal. -DePiep (talk) 12:07, 1 August 2020 (UTC)
More detailed talk on easy closure
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This is not an invitation for new discussion here, but a pointer to a new thread.
There are two essential issues around here: (1) what elements should be put in group 3 on Wikipedia, and (2) whether the navbox periodic table should be shown in 18 or 32 column format.
As new information has come in (a past IUPAC endorsement of the form with Lu under Y), I have started another thread below: Talk:Periodic_table#IUPAC:_an_endorsement_on_group_3_(1988). This is about the first issue (group 3 composition) only. I have endeavoured to keep it policy-based and drama-free.
To avoid confusing various issues, I suggest that the second issue about 32 vs 18 column be started in another new thread if anyone wants. I don't consider that very important myself, and therefore I have not started it. Double sharp (talk) 03:14, 2 August 2020 (UTC)
According to the final chronology of the first publications of the Mendeleev’s Periodic Table (Druzhinin, 2020[1]), the first Medneleev ‘s Table published March 26-27 [O.S. March 14-15] 1869 in the Mendeleev’s The Principles of Chemistry 1st Edition, and around March 17 [O.S. March 29] 1869 Mendeleev printed separate broadsheets with Periodic table - Attempt - to be sent to overseas scientists; April 17/19 for the first time the Mendeleev’ Periodic table was published in Europe in Journal für Praktische Chemie (in German)[2]
References
The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.
Should the default appearance of the periodic table on Wikipedia be changed to what it was in 2016, i.e. to have lutetium (71Lu) and lawrencium (103Lr) in group 3 rather than lanthanum (57La) and actinium (89Ac)? Or should it simply have markers below yttrium where all the lanthanides and actinides are supposed to go in? Double sharp (talk) 10:08, 20 July 2020 (UTC)
((Periodic table))
, ((Compact periodic table))
, the one in the infoboxes like ((infobox helium))
, etc. These normally appear as navigation aids in articles where the group 3 dispute is simply irrelevant, therefore unless someone has a better solution we seem to need to pick a default form for those. Double sharp (talk) 12:44, 20 July 2020 (UTC)Lu and Lr below Y. The form I propose, and which we had before 2016.
18-column:
H | He | |||||||||||||||||
Li | Be | B | C | N | O | F | Ne | |||||||||||
Na | Mg | Al | Si | P | S | Cl | Ar | |||||||||||
K | Ca | Sc | Ti | V | Cr | Mn | Fe | Co | Ni | Cu | Zn | Ga | Ge | As | Se | Br | Kr | |
Rb | Sr | Y | Zr | Nb | Mo | Tc | Ru | Rh | Pd | Ag | Cd | In | Sn | Sb | Te | I | Xe | |
Cs | Ba | * | Lu | Hf | Ta | W | Re | Os | Ir | Pt | Au | Hg | Tl | Pb | Bi | Po | At | Rn |
Fr | Ra | ** | Lr | Rf | Db | Sg | Bh | Hs | Mt | Ds | Rg | Cn | Nh | Fl | Mc | Lv | Ts | Og |
* | La | Ce | Pr | Nd | Pm | Sm | Eu | Gd | Tb | Dy | Ho | Er | Tm | Yb | ||||
** | Ac | Th | Pa | U | Np | Pu | Am | Cm | Bk | Cf | Es | Fm | Md | No |
32-column:
H | He | ||||||||||||||||||||||||||||||
Li | Be | B | C | N | O | F | Ne | ||||||||||||||||||||||||
Na | Mg | Al | Si | P | S | Cl | Ar | ||||||||||||||||||||||||
K | Ca | Sc | Ti | V | Cr | Mn | Fe | Co | Ni | Cu | Zn | Ga | Ge | As | Se | Br | Kr | ||||||||||||||
Rb | Sr | Y | Zr | Nb | Mo | Tc | Ru | Rh | Pd | Ag | Cd | In | Sn | Sb | Te | I | Xe | ||||||||||||||
Cs | Ba | La | Ce | Pr | Nd | Pm | Sm | Eu | Gd | Tb | Dy | Ho | Er | Tm | Yb | Lu | Hf | Ta | W | Re | Os | Ir | Pt | Au | Hg | Tl | Pb | Bi | Po | At | Rn |
Fr | Ra | Ac | Th | Pa | U | Np | Pu | Am | Cm | Bk | Cf | Es | Fm | Md | No | Lr | Rf | Db | Sg | Bh | Hs | Mt | Ds | Rg | Cn | Nh | Fl | Mc | Lv | Ts | Og |
La and Ac below Y. The current form.
18-column:
H | He | |||||||||||||||||
Li | Be | B | C | N | O | F | Ne | |||||||||||
Na | Mg | Al | Si | P | S | Cl | Ar | |||||||||||
K | Ca | Sc | Ti | V | Cr | Mn | Fe | Co | Ni | Cu | Zn | Ga | Ge | As | Se | Br | Kr | |
Rb | Sr | Y | Zr | Nb | Mo | Tc | Ru | Rh | Pd | Ag | Cd | In | Sn | Sb | Te | I | Xe | |
Cs | Ba | La | * | Hf | Ta | W | Re | Os | Ir | Pt | Au | Hg | Tl | Pb | Bi | Po | At | Rn |
Fr | Ra | Ac | ** | Rf | Db | Sg | Bh | Hs | Mt | Ds | Rg | Cn | Nh | Fl | Mc | Lv | Ts | Og |
* | Ce | Pr | Nd | Pm | Sm | Eu | Gd | Tb | Dy | Ho | Er | Tm | Yb | Lu | ||||
** | Th | Pa | U | Np | Pu | Am | Cm | Bk | Cf | Es | Fm | Md | No | Lr |
32-column:
H | He | ||||||||||||||||||||||||||||||
Li | Be | B | C | N | O | F | Ne | ||||||||||||||||||||||||
Na | Mg | Al | Si | P | S | Cl | Ar | ||||||||||||||||||||||||
K | Ca | Sc | Ti | V | Cr | Mn | Fe | Co | Ni | Cu | Zn | Ga | Ge | As | Se | Br | Kr | ||||||||||||||
Rb | Sr | Y | Zr | Nb | Mo | Tc | Ru | Rh | Pd | Ag | Cd | In | Sn | Sb | Te | I | Xe | ||||||||||||||
Cs | Ba | La | Ce | Pr | Nd | Pm | Sm | Eu | Gd | Tb | Dy | Ho | Er | Tm | Yb | Lu | Hf | Ta | W | Re | Os | Ir | Pt | Au | Hg | Tl | Pb | Bi | Po | At | Rn |
Fr | Ra | Ac | Th | Pa | U | Np | Pu | Am | Cm | Bk | Cf | Es | Fm | Md | No | Lr | Rf | Db | Sg | Bh | Hs | Mt | Ds | Rg | Cn | Nh | Fl | Mc | Lv | Ts | Og |
Markers below Y. The compromise form. IUPAC shows it on its periodic table, but they also plan to change it to one of the other forms. Which one has not been decided.
18-column:
H | He | ||||||||||||||||
Li | Be | B | C | N | O | F | Ne | ||||||||||
Na | Mg | Al | Si | P | S | Cl | Ar | ||||||||||
K | Ca | Sc | Ti | V | Cr | Mn | Fe | Co | Ni | Cu | Zn | Ga | Ge | As | Se | Br | Kr |
Rb | Sr | Y | Zr | Nb | Mo | Tc | Ru | Rh | Pd | Ag | Cd | In | Sn | Sb | Te | I | Xe |
Cs | Ba | * | Hf | Ta | W | Re | Os | Ir | Pt | Au | Hg | Tl | Pb | Bi | Po | At | Rn |
Fr | Ra | ** | Rf | Db | Sg | Bh | Hs | Mt | Ds | Rg | Cn | Nh | Fl | Mc | Lv | Ts | Og |
* | La | Ce | Pr | Nd | Pm | Sm | Eu | Gd | Tb | Dy | Ho | Er | Tm | Yb | Lu | ||
** | Ac | Th | Pa | U | Np | Pu | Am | Cm | Bk | Cf | Es | Fm | Md | No | Lr |
32-column (note the stretching of scandium and yttrium necessary):
H | He | ||||||||||||||||||||||||||||||
Li | Be | B | C | N | O | F | Ne | ||||||||||||||||||||||||
Na | Mg | Al | Si | P | S | Cl | Ar | ||||||||||||||||||||||||
K | Ca | Sc | Ti | V | Cr | Mn | Fe | Co | Ni | Cu | Zn | Ga | Ge | As | Se | Br | Kr | ||||||||||||||
Rb | Sr | Y | Zr | Nb | Mo | Tc | Ru | Rh | Pd | Ag | Cd | In | Sn | Sb | Te | I | Xe | ||||||||||||||
Cs | Ba | La | Ce | Pr | Nd | Pm | Sm | Eu | Gd | Tb | Dy | Ho | Er | Tm | Yb | Lu | Hf | Ta | W | Re | Os | Ir | Pt | Au | Hg | Tl | Pb | Bi | Po | At | Rn |
Fr | Ra | Ac | Th | Pa | U | Np | Pu | Am | Cm | Bk | Cf | Es | Fm | Md | No | Lr | Rf | Db | Sg | Bh | Hs | Mt | Ds | Rg | Cn | Nh | Fl | Mc | Lv | Ts | Og |
I spent some time making this issue understandable for any bystanders who may want to join in, helped by feedback from User:Dreigorich. As such, here is an explanation in the form of a dialogue. I have tried to keep answers very short. (The first version was a huge wall of text. Now it is not.)
The issue had its most recent reignition on Wikipedia in December 2019 and raged on through Wikipedia talk:WikiProject Elements/Archive 42, Wikipedia talk:WikiProject Elements/Archive 44, Wikipedia talk:WikiProject Elements/Archive 46, and until a few days ago Wikipedia talk:WikiProject Elements. I say "until a few days ago" because that's when I gave up the endeavour as fruitless: nobody seems about to have a change in opinion, and the arguments are raging in circles, and civility has been thrown out the window (and I realise now that I'm partly responsible for that, which I'm sorry for).
At that point we had exactly, among eight participants:
Since the issue was previously decided in an RFC back at Template talk:Periodic table, discussion between me and R8R concluded that going to another RFC would be the best way to propose it be changed back to how it was before the first RFC. Given that that RFC was over three years ago, and one of the main La proponents in it was me, and I've learnt enough new information since then that makes me think that the arguments I was propounding were wrong-headed, I think starting a new RFC is also most reasonable.
In theory one should get a neutral editor to write the background information. However, the problem is that this issue has something in common with many of the disputes at Wikipedia:Lamest edit wars. It is impossible to find a neutral editor to write background information because as soon as she looks at the issue enough to understand the background information, she takes a side herself and is no longer neutral. That is quite unusual given that Wikipedia:Lamest edit wars does not have a category for natural science, much less chemistry. Indeed, the main positive difference between the issue here and the ones over there is that so far there has not been any actual edit warring. Some uncivil remarks when people on either side get fed up, yes, and I am sorry that I have made some of them. But, thankfully, no edit warring.
So I wrote it. Even if I obviously have an opinion and am obviously supporting it with arguments here, I'm at least referring to reliable sources focusing on the issue to do it. If that is still not suitable, then this may at least be considered as a long explanation of my !vote rather than background information.
Q1: What are you arguing about?
Well, it turns out that somewhere near the bottom-left of the periodic table there's a bit of a dispute about which elements should go where.
Q2: Really? But I thought the periodic table was ancient history chemically speaking.
Yes, Mendeleev's first table dates from 1869. We still haven't sorted everything out, though. There are a bunch of elements that are rather difficult to place.
Q3: That sounds interesting. Tell me more.
In the words of Eric Scerri, "there's trouble at the beginning, middle and end of the periodic table". This RFC is about the middle: the rare earth elements.
Q4: So are you going to tell us what it is already?
It comes down to whether lutetium (Lu) or lanthanum (La) is a better fit for the position under yttrium (Y) in the periodic table. There's also a third form which has all fifteen lanthanides under yttrium, which we did have on WP a while ago, but not anymore.
Q5: Why is this so terribly important? If an element fits well in two places, why not duplicate it in both positions?
This is not generally done by reliable sources, except maybe when making a point. Therefore on Wikipedia we should not start doing it.
Q6: What about the "markers below yttrium" form? Isn't it a reasonable compromise?
It looks like one, but it is also a side in itself.
I do not support it for two reasons. One is technical. We sometimes use 32 column templates because they fit better as footers, e.g. ((compact periodic table))
, and then this approach becomes really problematic: scandium and yttrium have to stretch to cover 15 columns.
The other is chemical. This form claims that the f-block is a degenerate branch of the d-block and thus by extension that the f orbitals are a part of the valence core, which is simply false for almost all the elements involved (all but Lu and Lr, in fact). Every redox-capable f element (which is almost all of them) is obviously using its f electrons, and even those which are not seem to have some f contribution anyway (see Q22). See Jensen for a discussion. Maybe all the lanthanides are similar enough to fit below yttrium, but can anyone really claim that for the actinides?
Q7: Well, shouldn't we follow NPOV and show all three options all the time then?
That makes sense, and is what I support, when the group 3 controversy is the topic at hand. But usually it is not. Then you have to pick one to avoid going off on a tangent which is not relevant. Below I argue for Lu under Y.
For reasons of brevity, I will hence forth shorten the options' names to:
Q8: The things are called lanthanides and actinides. Shouldn't lanthanum and actinium continue to be used as the placeholders?
They're not placeholders. The * table and La table are different. Moreover, the whole point of the categories "lanthanide" and "actinide" is that those elements are similar to La and Ac. It seems quite weird to put La and Ac away from the rest of them. It is less weird for Lu (whose properties among the lanthanides are furthest from those of La) and not weird at all for Lr (which is quite unlike the other late actinides Es-No in properties).
Q9: IUPAC is the relevant source here, surely? What do they have to say?
They show their table as a * table, but they also state:
“ | While IUPAC has no recommendation for a specific form of the periodic table, i.e. 18-column or 32-column format, the version here presented is in the conventional long form and is yours to use. | ” |
— IUPAC Periodic Table website |
So it is not clear if that is an actual IUPAC recommendation for the * form or not.
IUPAC also organised a project to resolve precisely this issue, as can be seen from number 7 on their periodic table page. That project considers the La and Lu alternatives, but not the * one that they currently show. It started in 2015 and still has not concluded anything. Since it has both strong La and Lu proponents on it I also doubt it will conclude anything soon.
All we can conclude for now is that they seem to intend to deprecate the * form they currently show, thus leaving us without a firm guide in the meantime.
Q10: Why aren't we waiting for them then?
Because (1) I doubt that their work will be finished anytime soon, (2) we don't always follow IUPAC (we follow it for spelling aluminium but not for phosphane), and (3) any way you look at it, we have to show something in the meantime, see Q7.
I argue that we should look at the consensus of reliable sources that focus on the matter. Because an article focusing on group 3 and explaining why the authors think La or Lu should be there, I argue, outweighs in terms of reliability somebody who just draws a periodic table and gives no clue as to why he or she has drawn it that way. I claim that's in favour of Lu.
Q11: What do most reliable sources say?
Depends really. If you do a Google Image survey on "periodic table", * below Y dominates with proportions La:Lu:* of 1:1:4. The IUPAC project organised a survey that seems to show that La below Y dominates in textbooks (with La:Lu:* proportions of 4:1:1). However usually those textbooks have * in the same cell as La with a group 3 header above, therefore also implicitly claiming that the other lanthanides go there. So there is, at least, an ambiguity. Also, all these dominances are just 2/3 majorities, it's not a rare thing at all to find a textbook or periodic table poster giving Lu below Y.
I claim it's more relevant to look at what articles specifically focusing on this issue tell us, because it's common for textbooks to repeat standard errors on issues like this (e.g. claims that d orbitals are involved for phosphorus in PCl5, which are false but ubiquitous in textbooks), and most of these textbooks are hardly focusing on these heavy 4f and 5d elements that the dispute is all about. Those have a majority supporting the Lu form. I tallied them with Sandbh in an old submission to IUPAC we made on this matter in 2016; I've updated the list to 2020 below. Back then we agreed that La is better; then I changed my mind in response to new evidence from Droog Andrey that Lu is better, so we started arguing.
Advocates Lu | Advocates La | Advocates * |
---|---|---|
Bury (1921) Shemyakin (1932) Landau and Lifshitz (1958) Hamilton (1965) Merz and Ulmer (1967) Chistyakov (1968) Mathias (1971) Wittig (1973) Jensen (1982 and again 2015) Holden (1985) Fang et al. (2000) Horovitz and Sârbu (2005) Wulfsberg (2006) Ouyang et al. (2008) Scerri (2012) Nelson (2013) Settouti and Aouragi (2014) Alvarez (2020) |
Smith (1927) Trifonov (1970) Shchukarev (1974) Atkins (2006) Lavelle (2008) Restrepo (2017) Cao et al. (2020) |
Xu and Pyykkö (2016) |
Q12: Aren't you essentially claiming that a whole lot of eminent scientists are wrong?
It's a controversy. No matter which side you pick you're going to be claiming that a whole lot of eminent scientists are wrong. La advocates like Sandbh have Sergey Shchukarev on their side, Lu advocates like me have Landau and Lifshitz, so we can see that both options have had respected adherents. That's why I claim we have to look at the articles focusing on this issue and also consider the chemistry involved.
Q13: Many chemists have never heard that there was such a debate. Are you sure you're not just another fringe theory peddler?
Landau and Lifshitz are hardly "fringe". Neither is Clayden et al.'s Organic Chemistry, which has a Lu table. And Jensen, before his 1982 article, had not heard of this debate either.
Q14: What is the status of that interminable thread at Wikipedia talk:WikiProject Elements, stretching from last December to this July?
We have 5-1 for Lu and an extra two who at least think the La arguments proffered are problematic.
versus a single one:
However since we carried out the last change in an RFC, I feel (after discussion with R8R) that a proposed reversal should also go through an RFC. It seems only fair.
Q15: Have you addressed Sandbh's arguments there?
Yes, I responded to everything new he raised. Though not always in the most polite way after a few months of arguing, for which I am sorry.
Q16: Exactly why were you arguing this fiercely with Sandbh?
Well, he was writing an article, to be published in Foundations of Chemistry, that supports La under Y, and brought it to WT:ELEM for peer review last December. I and Droog Andrey disagreed with his arguments on what seemed to me to be logical grounds. Eventually it got to this:
“ | When you get as old as me, you'll learn there is much more to the world than logic. ...
You keep asking for a falsifiable theory. There isn't one! |
” |
— Sandbh, 07:49, 12 May 2020 (UTC) |
I found this quite surprising and responded in a rather too harsh manner, which I'm sorry for. Nevertheless I still cannot agree with this approach. Unless we use logic as a base, I don't see how we can judge the strength of arguments.
Q17: So why did it last so long?
Arguing with him was very helpful to sharpen my own understanding. But let's be honest: "someone is wrong on the Internet" also had something to do with it on my part, and I should really wean myself off of that.
Q18: But you've not been a complete angel yourself dealing with him.
That is true. I'm sorry. I will undertake to be more civil in future.
Q19: What's the history of this neverending argument anyway?
Mendeleev more or less gave up on placing the lanthanides, mostly leaving it to his Czech colleague Bohuslav Brauner. After some other attempts, eventually a form with all lanthanides under yttrium (basically the * form) was settled on. However even during this time tables that quite clearly don't put La under Y had already appeared (Henry Bassett 1892, Alfred Werner 1905). Actually Werner's form (yes, that's the father of coordination chemistry we're talking about) is incredibly close to the modern 32-column Lu form (with the exception that Be and Mg go over Zn instead of Ca). The only reason I do not call it a Lu table is because Lu had not yet been discovered(!).
In the 1920s and 1930s some chemists assigned Lu under Y because the chemistry of Y is more similar to Lu than La (Sc, Y, and Lu separate in the yttrium group of rare earths, but La and Ac in the cerium group).
The current dominance of the La form seems to stem, according to Jensen, from wrong electron configurations from the 1940s in which the lanthanides were assumed to be fn-1ds2 instead of fns2. These were later corrected, but by that time it seems the La form had stuck. We should not forget that these electron configurations are for the gas-phase ground state and are not really relevant for chemistry anyway (in chemical environments they change).
Meanwhile articles supporting Lu have appeared since 1921 and have been going on until the present; there have not been as many articles supporting La. Some authors have changed their periodic tables, others have not, there is still no consensus. IUPAC started a project in 2015 to look into it, they still have not made a decision.
It is possible that things will change. Be-Mg-Zn was present in Werner's periodic table of 1905, B-Al-Sc was once shown by Pauling(!), and prior to Seaborg it was generally accepted that the actinides known (Ac, Th, Pa, U) form a fourth d block row with uranium being eka-tungsten. Now you don't see any of these.
Q20: Should tradition count for something here?
There's not much of a tradition when chemists still argue about it. I prefer that we take the option that most of them who really analyse the issue support when we're not discussing the issue.
Q21: Would it not simply work if we just added footnotes like for helium where we explain that the other option is also common?
For the infobox, for the footer, you do not want to emphasise the issue where it is irrelevant, e.g. for the article on helium where group 3 matters not at all. The "overhang" the La table has in the 32 column form draws the eye's attention. The "stretchy scandium and yttrium" of the * table draws even more of the eye's attention. In order to make them look good, you have to use an 18 column instead of a 32 column form, which strikes me as not terribly good considering that those are supposed to be the same thing (just with the footnote glued in or not). So for these purposes I claim the Lu table is better: it preserves the symmetry. Moreover there is even scientific basis for preserving that symmetry, as the periodic table is explained by the valence orbitals and thus quantum mechanics, the Madelung rule having derived in the 1950s by Klechkovsky already.
Of course, whenever it is relevant (i.e. article of lanthanum, article of lutetium, and the period 7 congeners), we will add a note like there is for helium (about helium over beryllium being supported by some chemists). That goes without saying, for WP:NPOV reasons. But I think the reader would be better served with a Lu under Y default for when the situation does not matter.
Q22: OK, so are you going to get on to the scientific basis of this change or not?
Here are eight short arguments and the evidence behind them.
Everything said of the lanthanides above is also true or suspected of the corresponding actinides.
Evidence
For the 7th period elements no one has ever made more than a few atoms of, calculated properties have been used.
In general properties of Sc-Y-Lu match the d block trend better. Sc-Y-La matches the s block trend, but remember that group 3 is a d block group, and the s block groups are in fact anomalous: they break the trend of having no even-odd periodicity. (Even-period elements usually are more electronegative and more oxidising in higher oxidation states; odd-period elements act the opposite way. From 5d onwards relativistic effects make it not quite right, as 5d is electronegative but prefers higher oxidation states, and 7p is electropositive but prefers lower oxidation states. But mostly it is still correct as a generalisation.) That's because there's no contraction:
1s period I 2s 2p period II 3s 3p period III 4s 3d 4p period IV 5s 4d 5p period V 6s 4f 5d 6p period VI 7s 5f 6d 7p period VII
From the build-up of the periodic table we see that for non-s blocks, even periods either have the first orbital of a given angular momentum (which is smaller than expected), or they have suffered a new contraction that wipes out the expected increase of radius and basicity (3p-4p increase wiped out by 3d, 4d-5d increase wiped out by 4f, 5p-6p increase wiped out both by 4f, 5d, and relativistic contraction of 6s). The s block is an exception: it always sits right above the noble gas core and never has any incomplete shielding effects (except a tiny bit for 2s vs 3s, and the obvious massive exception of 1s). There's no reason why any other group should follow them.
1st ionisation energies of the elements. Lu and especially Lr fall off the trends of the lanthanides and actinides respectively, and fit better with the trends of the succeeding 5d and 6d transition metals.
3rd ionisation energies of the transition elements (makes sense, having ionised the s electrons away already, and now probing the energies to remove a d or an f electron). This is not perfect, but when the configuration is "wrong", the "right" one is usually so close that it doesn't matter. La2+ is [Xe]5d1, but the expected [Xe]4f1 is about 0.89 eV up in energy; Gd2+ is [Xe]4f75d1, but the expected [Xe]4f8 is about 0.30 eV up in energy. I hope we agree that this is small potatoes compared to the differences between neighbouring elements.
Natural families La-Eu and Gd-Yb are supported, following Sc-Mn and Fe-Zn; the half-full and full subshell gives a local maximum in energy, because the next electron going in is either paired (after half-full) or in a higher-energy subshell (after full) and is then easier to remove. The effect weakens for higher rows (as you can see from the 1st IE chart as well; N-O is an obvious blip downward, P-S is not so obvious, by Sb-Te it doesn't go down anymore), but you can still see it.
property | La | Lu | Hf | Ta | W | Re | Os | Ir | Pt | Au | Hg |
---|---|---|---|---|---|---|---|---|---|---|---|
m.p. (K) | 1193 | 1925 | 2506 | 3290 | 3695 | 3459 | 3306 | 2719 | 2041.4 | 1337.33 | 234.43 |
b.p. (K) | 3737 | 3675 | 4876 | 5731 | 5828 | 5869 | 5285 | 4701 | 4098 | 3129 | 629.88 |
specific heat capacity (J/(g*K)) | .195 | .154 | .144 | .14 | .132 | .137 | .13 | .131 | .133 | .129 | .14 |
EN (Pauling) | 1.1 | 1.27 | 1.3 | 1.5 | 2.36 | 1.9 | 2.2 | 2.2 | 2.28 | 2.54 | 2.0 |
EN (Kulsha-Kolevich) | 1.11 | 1.31 | 1.38 | 1.46 | 1.54 | 1.55 | 1.67 | 1.75 | 1.84 | 1.93 | 1.81 |
Density | 6.145 | 9.84 | 13.31 | 16.654 | 19.25 | 21.02 | 22.61 | 22.56 | 21.46 | 19.282 | 13.5336 |
Young's modulus | 36.6 | 68.6 | 78 | 186 | 411 | 463 | ??? | 528 | 168 | 78 | ??? |
Bulk modulus | 27.9 | 47.6 | 110 | 200 | 310 | 370 | 462 | 320 | 230 | 180 | 25 |
Resistivity (nΩm, close to r.t.) | 615 | 582 | 331 | 131 | 52.8 | 193 | 81 | 47.1 | 105 | 22.14 | 960 |
Brinell hardness (MPa) | 350-400 | 893-1300 | 1450-2100 | 441-3430 | 2000-4000 | 1320-2500 | 3920-4000 | 1670 | 310-500 | 188-245 | ??? |
Heat of fusion (kJ/mol) | 6.20 | 22 | 27.2 | 36.57 | 52.31 | 60.43 | 57.85 | 41.12 | 22.17 | 12.55 | 2.29 |
In most properties Lu matches the properties of the 5d elements better than La. That is also true for chemical properties (Lu is less basic and less big as a cation, matching 5d elements better), but those are harder to show as data. ^_^
property | Ac | Lr | Rf | Db | Sg | Bh | Hs | Mt | Ds | Rg | Cn |
---|---|---|---|---|---|---|---|---|---|---|---|
m.p. (K) | 1323 | 1900 | 2400 | ??? | ??? | ??? | ??? | ??? | ??? | ??? | 283 |
EN (Kulsha-Kolevich) | 0.97 | 1.29 | 1.34 | 1.41 | 1.49 | 1.59 | 1.72 | 1.83 | 1.92 | 1.99 | 1.91 |
Density (g/cm3) | 10.07 | 15.6 | 23.2 | 29.3 | 35.0 | 37.1 | 40.7 | 37.4 | 34.8 | 28.7 | 14.0 |
1st IE (kJ/mol) | 499 | 470 | 580 | 665 | 757 | 740 | 730 | 800 | 960 | 1020 | 1155 |
3rd IE (kJ/mol) | 1900 | 2228 | 2300 | 2378 | 2484 | 2570 | 2830 | 2900 | 3030 | 3080 | 3160 |
The little known and predicted about Ac vs Lr-Cn seems to show the effect is even stronger. All bulk properties of Lr-Cn are of course predictions as nobody has ever made enough. Kulsha-Kolevich electronegativity was used because no other scale actually seems to have values for elements as heavy as copernicium.
property | Ac | Th | Pa | U | Np | Pu | Am | Cm | Bk | Cf | Es | Fm | Md | No | Lr |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1st IE (kJ/mol) | 499 | 587 | 568 | 598 | 605 | 585 | 578 | 581 | 601 | 608 | 619 | 627 | 635 | 642 | 470 |
3rd IE (kJ/mol) | 1900 | 1978 | 1814 | 1900 | 1997 | 2084 | 2132 | 2026 | 2152 | 2267 | 2334 | 2363 | 2470 | 2643 | 2228 |
m.p. (K) | 1323 | 2115 | 1841 | 1405 | 917 | 913 | 1449 | 1613 | 1259 | 1173 | 1133 | 1125 | 1100 | 1100 | 1900 |
EN (Kulsha-Kolevich) | 0.97 | 1.01 | 1.04 | 1.06 | 1.08 | 1.12 | 1.07 | 1.18 | 1.22 | 1.27 | 1.32 | 1.36 | 1.39 | 1.37 | 1.29 |
Density (g/cm3) | 10.07 | 11.72 | 15.37 | 18.95 | 20.45 | 19.84 | 13.69 | 13.51 | 14.79 | 15.1 | 8.84 | 9.7 | 10.3 | 9.9 | 15.6 |
Lawrencium's properties, as far as they are predicted, seem to be a quite bad match for the late actinides. (Data for Fm through Lr bulk properties is predicted, no one has ever made enough.)
M | Ca | Sc | Ti | V | Cr | Mn | Fe | Co | Ni | Cu | Zn | Ga | Ge |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
mp (°C) | 842 | 1541 | 1668 | 1910 | 1907 | 1246 | 1538 | 1495 | 1455 | 1085 | 420 | 30 | 938 |
bp (°C) | 1484 | 2836 | 3287 | 3407 | 2482 | 2061 | 2861 | 2927 | 2730 | 2562 | 907 | 2400 | 2833 |
M | Ba | La | Ce | Pr | Nd | Pm | Sm | Eu | Gd | Tb | Dy | Ho | Er | Tm | Yb | Lu | Hf |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
mp (°C) | 727 | 920 | 795 | 935 | 1024 | 1042 | 1072 | 826 | 1312 | 1356 | 1407 | 1461 | 1529 | 1545 | 824 | 1652 | 2233 |
bp (°C) | 1633 | 3464 | 3443 | 3130 | 3074 | 3000 | 1900 | 1529 | 3000 | 3123 | 2567 | 2600 | 2868 | 1950 | 1430 | 3402 | 4603 |
Double periodicity in melting and boiling points likewise supports La-Eu and Gd-Yb as natural f-block subfamilies. (When we get to a half-filled or filled subshell, delocalisation of those electrons becomes less favourable.) The effect is weaker for succeeding rows as usual.
M | Ca | Sc | Ti | V | Cr | Mn | Fe | Co | Ni | Cu | Zn | Ga |
---|---|---|---|---|---|---|---|---|---|---|---|---|
M3+/M2+ potential | very high | −2.3 | −0.9 | −0.255 | −0.42 | +1.56 | +0.771 | +1.92 | +2.3 | +2.4 | very high | −0.8 |
M | Sr | Y | Zr | Nb | Mo | Tc | Ru | Rh | Pd | Ag | Cd | In |
M3+/M2+ potential | very high | −2.8 | ??? | −0.9 | −0.2 | +0.3 | +0.24 | +0.7 | ??? | +1.8 | very high | −0.49 |
M | Ba | La | Ce | Pr | Nd | Pm | Sm | Eu | Gd | Tb | Dy | Ho | Er | Tm | Yb | Lu |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
M3+/M2+ potential | very high | −3.1 | −3.2 | −3.1 | −2.7 | −2.6 | −1.55 | −0.35 | −3.9 | −3.7 | −2.6 | −2.8 | −3.0 | −2.2 | −1.05 | −2.7 |
M | Ra | Ac | Th | Pa | U | Np | Pu | Am | Cm | Bk | Cf | Es | Fm | Md | No | Lr |
M3+/M2+ potential | very high | −4.9 | −4.9 | −5.0 | −4.7 | −4.7 | −3.5 | −2.3 | −3.7 | −2.8 | −1.6 | −1.3 | −1.1 | −0.1 | +1.4 | −2.6 |
The standard reduction potential trends across the two subfamilies La-Eu and Gd-Yb are smooth, like those of Sc-Mn and Fe-Zn; they reach maxima at the half-filled and filled subshell elements as expected as then it is more difficult to ionise an extra electron past the half-filled or filled subshell. Same goes for 3rd ionisation energies, and same goes for melting and boiling points (more difficult to delocalise those electrons).
We use +2 oxidation states as a baseline to compare like with like: this way the s electrons are ionised, the configurations involved are (almost always!) dn and fn, when they are not the difference in energy to that is usually small enough to ignore, and we can probe the stabilising effect of the real half-filled and filled shell. Of course you may artificially shift to the +3 state and get different results, but it has about as much meaning as plotting 2nd ionisation energies to "prove" that the periods should go from group 2 to group 1:
element | He | Li | Be | B | C | N | O | F | Ne | Na | Mg | Al | Si | P | S | Cl | Ar | K | Ca |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
2nd IE (kJ/mol) | 5250.5 | 7298.1 | 1757.1 | 2427.1 | 2352.6 | 2856 | 3388.3 | 3374.2 | 3952.3 | 4562 | 1450.7 | 1816.7 | 1577.1 | 1907 | 2252 | 2298 | 2665.8 | 3052 | 1145.4 |
I hope we can agree that this is self-evidently absurd.
Conclusion
For these reasons I claim that the La form has no scientifically sound basis. It is not a good chemist's periodic table because yttrium is closer to lutetium than lanthanum, and because lutetium and lawrencium are far more like transition metals than lanthanum and actinium. It is not a good physicist's periodic table, because it goes away from the blocks that underlie the periodic table. And clearly teaching the Madelung rule is going to be pedagogically better than teaching the Madelung rule and then giving an exception for La that doesn't even match reality, given its 4f involvement.
This matches the criteria for putting elements in the periodic table as stated by Jensen, particularly arguments 2 and 3 (4f in La and its complete lack in Lu).
“ | In actual fact, when assigning an element to a position in the periodic table the above factors are not simply applied as a haphazard empirical blend or combination, rather they are applied in a strictly hierarchical order, consisting of four steps or stages (Jensen 2009):
|
” |
— William B. Jensen (2015), The positions of lanthanum (actinium) and lutetium (lawrencium) in the periodic table: an update |
Q23: Are there any other La arguments that you haven't refuted above?
Sandbh seems to believe in the importance of the "differentiating electron" of an element, which is the electron that differentiates it in its ground-state gas-phase configuration for the previous element. For example, since titanium is [Ar]3d24s2 (ground-state gas-phase), and vanadium is [Ar]3d34s2 (same), vanadium has a 3d differentiating electron.
I do not see why this should be important, given that we are not generally in the business of building elements up by adding one proton and one electron from the previous one. Also differentiating electrons are for the gas phase, and we've already discussed above that this is not relevant for chemistry because atoms usually have a different configuration when chemically bound from what they have sitting alone by themselves. Neither is it that clear all the time what exactly the differentiating electron ought to be. Passing from vanadium [Ar]3d34s2 to chromium [Ar]3d54s1 we have added two 3d electrons and subtracted one 4s one.
But all right, suppose we grant that. A usual argument Sandbh gives for why this should supposedly be important is looking at silver. It has a 5s differentiating electron as opposed to the 5d one of its heavier homologue gold, and this supposedly explains why the chemistry of silver is more main-group-like than gold:
“ | [Double sharp has argued that] Differentiating electrons make no difference to the chemistry of the elements and are therefore irrelevant. In fact, a counterexample is silver, the d/e of which is expected to be a d-type, but in fact turns out to be an s-type. Silver then acts predominately as a main-group metal rather than a transition metal. ... --- Sandbh (talk) 03:01, 15 July 2020 (UTC) | ” |
On the other hand, technetium also has a 5s differentiating electron as opposed to the 5d one of its heavier homologue rhenium. Judging by how happy technetium is to interconvert between its many oxidation states like the transition metal it really is, this does not seem to do anything at all to make it more main-group-like at all.
If you look at KCl, CaCl2, ScCl3, and TiCl4, the first three are ionic solids and the last one is a volatile liquid. So group 3 has to be cleft from group 4.
I used to believe this, but it doesn't really work. We may equally well observe the melting points of Cs2O, BaO, La2O3 or Lu2O3, HfO2, Ta2O5, WO3, Re2O7, OsO4. These are all high melting-point compounds until WO3, and the melting points keep increasing (showing ionic character) until HfO2. And we can multiply other counterexamples like Na2O, MgO, Al2O3, SiO2 (melting points increase till MgO).
Any way you look at it, this doesn't support any natural group divide at all. Mostly because there is no such thing outside the fundamental one (noble gas | alkali metal).
A related argument states that group 3 is more similar to group 2 than group 4 because group 3 acts like a trivalent version of the main group metals. But for group 4 you can find aqueous cations with noble gas configurations that make them like a tetravalent version. Simply make the pH low enough. −1 will do, you'll easily find things like Zr4+ and Hf4+, maybe even Ti4+, then. Well, look at Fajans' rules again. Cation polarising power, hence acidity, depends on charge and radius. Following Gary Wulfsberg's Principles of Descriptive Inorganic Chemistry, the usual dependence is on charge squared divided by ionic radius. We can then draw his table:
Z2/r ratio | Pauling EN | Category | pKa | Examples |
---|---|---|---|---|
0.00–0.01 | <1.8 | Nonacidic cations | 14–15 | Most +1 ions in s block |
0.01 | >1.8 | Feebly acidic cations | 11.5–14 | Tl+ |
0.01–0.04 | <1.8 | Feebly acidic cations | 11.5–14 | Most +2 ions in s, f blocks |
0.01–0.04 | >1.8 | Weakly acidic cations | 6–11.5 | Most +2 ions in d block |
0.04–0.10 | <1.8 | Weakly acidic cations | 6–11.5 | All +3 ions in f block |
0.04–0.10 | >1.8 | Moderately acidic cations | 1–6 | Most +3 ions in d block |
0.10–0.16 | <1.8 | Moderately acidic cations | 1–6 | Most +4 ions in f block |
0.10–0.16 | >1.8 | Strongly acidic cations | (−4)–1 | Most +4 ions in d block |
0.16–0.22 | <1.8 | Strongly acidic cations | (−4)–1 | |
>0.16 | >1.8 | Very strongly acidic cations | <−4 | |
>0.22 | <1.8 | Very strongly acidic cations | <−4 |
And indeed, we find that while the group 4 cations are indeed strongly acidic, they are not so acidic that they react irreversibly with water: the pKa is not quite low enough. Sure, you'll soon get a precipitate if their cations are introduced to aqueous solution at all but pretty low pH. But you can redissolve that precipitate in concentrated hydrochloric acid, at least if it hasn't aged too much. It's cations like Nb5+ and Ta5+ that are "very strongly acidic": too acidic to exist in water at all. So, apparently the group divide is really between groups 4 and 5 instead.
But probably the clearest way to rebut this whole idea is to look at what happens in the p block. Group 13 metals Ga, In, Tl can form aqueous cations in their group oxidation state. Group 14 metals Ge, Sn, Pb cannot, they are too acidic. (Remember what I said before? Elements in higher oxidation states are more electronegative and hence more acidic, whence how Pd2+ is more acidic than Be2+.) So this seems to also support B-Al-Sc if you apply it consistently. I think that is not a good sign.
The chemistry of group 3 is not more similar to that of group 2 to group 4, so that justification is also out. Observe the aqueous chemistry of group 4 and the organometallic chemistry of group 3. Not to mention that the standard "transition metal" property everyone knows from high school is forming coloured paramagnetic compounds with incomplete d orbitals. If you think scandium should be disqualified, because you will have a tough time finding stable lower-oxidation state compounds of Zr-Hf-Rf in group 4 and Nb-Ta-Db in group 5, those suddenly are also in danger of being disqualified. And as for the other s-block property of forming hard, class-A cations – the elements up to group 6 show that. Everything is a continuum here, and transition properties are no exception: they go in slowly, they come out slowly. All peripheral groups in blocks have properties similar to their block neighbours, there's no reason why to emphasise the property this much for group 3.
According to this argument, lanthanum cannot start the f block because La3+ fails to have an f electron, and there is complete regularity down Ce3+ to Lu3+ in showing f1 to f14. But such a common stable oxidation state for everybody only exists in the f block, and actually only the 4f elements, not the 5f ones. So this argument is about as local as you can get and doesn't work as part of the periodic law.
I also note that by this logic La cannot be in the d block either, since La3+ is d0. In fact it cannot be anywhere in the periodic table either, since La3+ is also s0 and p0. And there are no s block elements either except helium (the least s-block-like of them), because in their common oxidation states (+1 for the column H-Li-Na-K-Rb-Cs-Fr, +2 for Be-Mg-Ca-Sr-Ba-Ra) they are all s0. Why should we use criteria that only apply to one block?
Finally, La had been [Xe]4f16s2, all this argument would surely never have started: a La-Yb f block (i.e. a Lu table) would be absolutely standard. But it would still lose the f electron in the +3 state anyway, so this argument would still argue for Ce-Lu anyway. That seems hard to accept.
According to this argument, advanced by Lavelle, La and Ac cannot be put in the f block because they would represent the only case of two elements going into a block with no outer electrons in common with their block.
Of course, this is predicated on the gas-phase ground-state configurations, which is not that relevant. Also, how does this deal with Lu and Lr? Neither of them have any outer f electrons, they also form a pair out of place. So the argument is as much for the Lu table as it is for the La table.
Q24: Weren't you on the other side of this last time?
Indeed. I learnt more, I changed my mind. All thanks to Droog Andrey (= A. V. Kulsha). You may enjoy the periodic table poster he and one of his colleagues created too (link is to version of 2019). ^_^
Q25: So what's wrong with the old arguments that you were using then?
I've addressed them all above.
Q26: So how do I know you won't be fervently arguing to change it back again in four years?
I don't, that's because I believe in the scientific method. If I find out something falsifying my stand, I change my mind. You can argue it if you want... ;)
Q27: Why now? Why not wait for IUPAC?
It's not possible to be neutral. Sc-Y-* is also a side. I also think Sc-Y-* is chemically just weird (those f electrons are not core electrons, and while asking La-Lu to share one flat makes some sense, it's really weird for Ac-Lr), and Jensen agrees.
Q28: Why start it now and not earlier?
Because my ideas about this were not clear enough till this round of argument with Sandbh started. Now they are.
Q29: Do you have nothing better to do than write long screeds here about this?
Well, at R8R's suggestion it is now behind a collapse box, and most of the long screeds have been replaced by very short answers.
Q30: Do you have anything against Sandbh personally?
No, I just find myself in disagreement with his stand on logic and falsifiability.
@ComplexRational, DePiep, Droog Andrey, Officer781, R8R, Sandbh, Дрейгорич, AzaToth, Tazerdadog, Maproom, CuriousMind01, Silvio1973, and Timtempleton: Pinging all megathread and previous RFC participants. And also AnthonyDu0122 who raised it above. ^_^
I object, in the strongest possible terms, to the way Double sharp initiated this RFC.
I allege that Double sharp's background to the RFC is biased; incomplete; out-of-context; contains inappropriate content; and—at 33,000 words—is too long for anyone to gain an informed understanding of the issue at hand. This follows other unacceptable behaviour alluded to on his part, including his hack work on our periodic table article; removing some of my citation supported content; slandering me; swearing; and effectively demanding I provide a falsifiable hypothesis when I was under no obligation to do so.
The context for my objection is my long-term participation in the Group 3 debate, including two submissions to IUPAC on the matter, one with Double sharp (which he has now dissociated himself from).
My other objection is that an article written by me will soon appear in the journal Foundations of Chemistry, entitled "The location and composition of Group 3 of the periodic table". I have the proofs in hand. The article has been reviewed by three PhDs and accepted for publication by Eric Scerri, a world authority of the periodic table. Scerri is also the chair of the IUPAC Group 3 project.
Double sharp knows all this, yet chooses to go ahead with the RFC. So much for taking into account "reliable sources that focus on the matter." So much for extending me the courtesy of professional respect. So much for working collegiately within WP:ELEMENTS.
Here again is a continuation of his pattern of unacceptable behaviour.
Most of the rest of the editors who have voiced their opinions for Lu, it seems to me, do so on the basis of a personal preference or a very limited grasp of the full extent of the arguments and literature involved in this case.
I'm not holier than anyone. I do claim, along with Double sharp, to have maintained a depth of familiarity and interest in this question since at least 2016. In my case I've been arguing the question with Scerri, on and off, since 2008. And along the way, Double sharp and I have changed our minds about Group 3 as we both learnt new things along the way.
As Jones (2010) has written:
As Schwerdtfeger, Smits & Pyykkö (2020) wrote:
That is why we have an IUPAC Group 3 project team, to assess the literature and address these unnecessary disputes.
And the IUPAC project team has reported that, based on a survey of chemistry textbooks and other sources, that the La form dominates by a 4:1:1 margin, where the two 1's are the *-** form and the Lu form.
As Scerri wrote:
As WP:Elements member R8R wrote:
Precisely.
The way ahead, as I see it, is (1) cancel the RFC until my article appears on line; and (2) Double sharp and I to agree on a balanced introduction to a new RFC, should Double sharp wish to proceed with another RFC. Failing this I will take up the matter on WP:AN. --- Sandbh (talk) 03:27, 21 July 2020 (UTC)
“ | Given these points I would like to propose that although there is no objective way to distinguish the tables shown in figures 10 and 12 [Lu and La respectively] one should nevertheless opt for the former of these as the official IUPAC periodic table. The factors that might lead us to favoring figure 10 have already been mentioned. They are that the d-block of the periodic table remains unified and intact, whereas the table in figure 12 requires that the d-block be separated into two highly uneven portions consisting of one and nine groups respectively. | ” |
— Scerri ER 2020, "Recent attempts to change the periodic table", Philosophical Transactions A, here |
Here is what Double sharp neglects to mention.
Mathias (1969) grumbled about La in group 3 being the most popular form. Myers, Oldham and Tocci (2004, p. 130) found La and Ac to be the most popular form of periodic table, a sentiment echoed by Clarke and White (2008); and Lavelle (2008; 2009). My article (Vernon 2020) will reiterate this.
As noted, IUPAC and Scerri have confirmed this. Double sharp knows it but neglects to mention it. There is no support in the literature for his WP:OR interpretation.
Scerri has noted (pers. comm.) that he distinguishes between his personal view as a chemist, and his role as the chair of the IUPAC Group 3 committee. Once again Double sharp demonstrates that he does not know what is going on here.
I reject Double sharp's assertion that it would not be possible for is to reach agreement on a balanced approach to an RFC. Once again he resorts to unwarranted—act of desperation—escalation i.e. 1. the hack work on our periodic table; 2, this RFC; 3. unilateral escalation to WP:AN. 08:05, 21 July 2020 (UTC)
@Double sharp: So, are we going to cancel this RFC and come up with an NPOV version, suitable for another RFC post online publication of my article, or are you going to waste everyone's time and some poor WP:ADMIN's? Sandbh (talk) 08:19, 21 July 2020 (UTC)
((Periodic table))
(See top of this RFC thread). We should stick to the same version as IUPAC currently endorse, i.e. IUPAC (2018-12-01). "PERIODIC TABLE OF ELEMENTS". since that's what most readers would expect. (Even British chemists don't use sulphur now, only sulfur.) Michael D. Turnbull (talk) 13:49, 20 July 2020 (UTC)
((Compact periodic table))
etc. Will scandium and yttrium have to be stretched over 15 columns? The only way it becomes less awkward is if we change those to the 18-column form too. Which is a bit odd as the 18 and 32 column forms are supposed to be saying the same thing in a different layout. Double sharp (talk) 13:56, 20 July 2020 (UTC)The table is not periodic. The elements are. The correct name is the table of periodic elements. Chemistry is a precise science and it seems incredible that every chemist in the English speaking community has overlooked this for 150 years.
The Table of Periodic Elements should replace the improper but universal Periodic Table of The Elements.
This is my original finding based on the rule that an adjective modifies the immediately following noun, viz., table.
I am the source, John Jaeger, Irvine, California. — Preceding unsigned comment added by SpiderMBA (talk • contribs) 21:38, 9 September 2020 (UTC)
That expression is rarely found in the literature. For a 1994 example: “Pure elements being electroplated are numerous. Fig. 4 shows in a Mendele'v table of periodic elements, those elements (bold) which can be electrodeposited from aqueous solutions.” doi:10.1080/00202967.1994.11871029
That said, the elements do not show periodicity or an approximate repetition of properties until they are ordered according to their atomic number. Once so ordered the sequence can be arranged into e.g. a table or a spiral or a pyramid, and so on. Since periodicity is not an intrinsic property of the elements such as e.g. density or ionisation energy or electron affinity, the convention is to associate the adjective (periodic) with the arrangement (table, circle, octagonal prism, whatever) rather than the elements, since it is the arrangement that crystallises periodicity, not the other way round. Sandbh (talk) 12:01, 13 September 2020 (UTC)