Talk:Extended periodic table

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Can you define a p1/2 subshell?? Georgia guy (talk) 19:42, 15 October 2015 (UTC)

From ununseptium (and the hypothetical elements would experience this effect even more strongly): "The spin–orbit interaction is especially strong for the superheavy elements because their electrons move faster—at velocities comparable to the speed of light—than those in lighter atoms. In ununseptium atoms, this lowers the 7s and the 7p electron energy levels, stabilizing the corresponding electrons, although two of the 7p electron energy levels are more stabilized than the other four. The stabilization of the 7s electrons is called the inert pair effect; the effect that separates the 7p subshell into the more-stabilized and the less-stabilized parts is called subshell splitting. Computational chemists understand the split as a change of the second (azimuthal) quantum number l from 1 to 1/2 and 3/2 for the more-stabilized and less-stabilized parts of the 7p subshell, respectively." This is where the names "p1/2" and "p3/2" come from: the subscript denotes the azimuthal quantum number of the orbital. Double sharp (talk) 14:47, 20 October 2015 (UTC)
I understand this as meaning that the "p1/2" subshell is actually a new kind of orbital halfway between s and p and should be called "s and a half", and that "p3/2" is likewise halfway between p and d and is thus "p and a half". Georgia guy (talk) 15:03, 20 October 2015 (UTC)

Two kinds of superactinides[edit]

Can anyone distinguish the g-block from the f-block in the eighth row rather than calling both of them "superactinides"?? Georgia guy (talk) 22:47, 13 November 2015 (UTC)

They can be distinguished by calling it 5g series or g-block series and 6f series. PlanetStar 00:20, 14 November 2015 (UTC)
There isn't expected to be much of a chemical difference between how the two behave, so why should they have separate terms? Additionally, this far into the periodic table, the blocks shouldn't mean much. Double sharp (talk) 11:43, 14 November 2015 (UTC)
This may be what you're talking about, or it may be completely different: in the chart in the "History" section, the label color for Super­actinides and Predicted are exactly the same. Maybe they're ALL predicted (I'm a designer, not a scientist) but I wouldn't know that by looking at the chart. I don't know if Wikipedia has any sort of standard colorization scheme, so I'll just leave it up to someone more knowledgeable than myself to change it, but it should be changed. BevansDesign (talk) 16:10, 12 January 2016 (UTC)

Any thoughts on something like this??[edit]

The alkali metal article says:

Although a simple extrapolation of the periodic table would put element 169, unhexennium, under ununennium, Dirac-Fock calculations predict that the next alkali metal after ununennium may actually be element 165, unhexpentium, which is predicted to have the electron configuration [Uuo] 5g18 6f14 7d10 8s2 8p1/22 9s1.

I would like to know if anyone objects to a statement like the following in an appropriate section of this article:

Although a simple extrapolation of the periodic table would put the elements after 120 as follows: 121-138 form the g-block superactinoids; 139-152 form the f-block superactinoids, 153-162 would be transition metals; 163-166 p-block metals; 167=halogen; 168=noble gas; 169=alkali metal; 170=alkaline earth metal, Dirac-Fock calculations predict that it will most likely go: 121-140 form the g-block superactinoids; 141-154 form the f-block superactinoids; 155-164 form the transition metals; 165=alkali metal; 166=alkaline earth metal; 167-170 p-block metals; 171=halogen; 172=noble gas.

Any thoughts on where a statement like this can go in the article?? Georgia guy (talk) 15:20, 16 November 2015 (UTC)

Since that simple extrapolation was Seaborg's, this sort of statement could fit very well in an expanded and rewritten "History" section. Double sharp (talk) 05:03, 17 November 2015 (UTC)


What is special about 184 that makes it the highest atomic number to mention in this article?? Is there a proof that it's impossible (not just difficult, but impossible) to find the atomic number of the highest eka-superactinide?? Georgia guy (talk) 18:45, 8 December 2015 (UTC)

Because that's as far as anyone has carried out the calculations. Beyond that, nobody knows yet. Double sharp (talk) 05:58, 6 January 2016 (UTC)
...which in turn is because... Georgia guy (talk) 14:00, 6 January 2016 (UTC)
I think "nobody knows yet" is to say: "nobody made calculated predictions yet". And maybe (I'm just thinking out loud) near E184 'tradidional' buildup of heavier elements may be affected/limited by relativity limits. Like, electron #185 would need to exceed the speed of light. -DePiep (talk) 07:02, 7 January 2016 (UTC)
Because it's not cool? Elements with sub-second half-lives are not generally considered cool to my knowledge, unless they are expected to be alkali metals, in which case they will appear copiously in YouTube comments (though not as often as francium). We don't really know what happens beyond 173 anyway. These predictions for 184 would be valid if you could construct it without weird things happening, but beyond 173 there may be weird things happening, and we are not really sure yet. Double sharp (talk) 07:52, 7 January 2016 (UTC)


The eka-superactinoids were removed from the template displaying the extended periodic table per consensus. But the article still has a section about the eka-superactinoids. Any discussion about whether we should remove that section?? Georgia guy (talk) 02:02, 10 January 2016 (UTC)

I've drastically cut it down, removing the detailed information about Fricke's predictions on E184, since they will likely not come to pass. It still is interesting as a historical speculation, fueled by thinking that 184 was a proton magic number (though it seems that 164 is a more likely candidate now). Double sharp (talk) 13:36, 10 January 2016 (UTC)

Why 7d-elements are 155-164 instead of 157-166?[edit]

First of all, a criterion to select a group number is not the number of d-electrons but the number of valence electrons including d-shell. We have 7d109s0 for element 164 as well as 4d105s0 for palladium; elements from 157 to 162 has from 3 to 8 valence electrons (over closed 5g186f148s28p2 shell), as well as elements from lutetium to osmium (over closed 4f14 shell).

Secondly, elements 165 and 166 seem to be too far from being alkali and alkali-earth metals. The soft 7d subshell under valence 9s electrons makes these elements similar to silver and cadmium, and maybe both of them (or at least element 165) could still use their 7d electrons for chemical bonding.

Thirdly, elements 155 and 156 have their 6f subshell still opened for chemical bonding, making them similar to mendelevium and nobelium, so they shouldn't count as 7d-elements.

To make all of that clear, let's remember that all of these elements are metals, so their chemical nature is better described by electronic structure of their cations instead of neutral atoms. When atom is positively ionized, a few things happen:

  • subshells with higher l number are generally drowned deeper because of less screening, e.g. for Ca2+ 3d lies below 4s, while for neutral Ca 3d lies above 4p;
  • atomic levels become less dense, making core, valence and free subshells easier to distinguish;
  • those exceptions from Madelung's rule which has no chemical significance (e.g. for Cr, Cu, Nb-Pd, Pt, Lr) are vanished.

Thus, for metals the periodic trends are far better described by configurations of dications instead of neutral atoms (after element 122 the given configurations may appear a bit higher than the ground state, but at least they are close to the ground state).

a proposed look of periodic table

That's why I propose a somewhat simpler and less detailed template for extended periodic table, looking like this:

Note that it has little sense trying to separate 5g and 6f blocks since both of them has quite uncertain starting bounds. However, the 18-electron capacity of 5g yields some correlations along two subsets 121-138 and 139-156 since both of them have 18-element length. Elements of the subset 121-138 have up to 6 valence electrons (like 6f28s28p2 with 8s2 gradually drowning into the core) and are very similar just like lanthanides overall, while the subset 139-156 reminds actinides: first elements has an increasing number of valence electrons (6fk7d28p2), but then 6f subshell is buried down along with 8p, leaving only 7d2 electrons easy to remove (as well as 7s2 electrons in nobelium).

After all, that's not an original research: the corresponding model was introduced in 2006 by Nefedov; here's the paper:

So, again, I propose that simple model with elements 157-172 belonging to groups 3-18 as the best guess to their chemical nature, and elements 121-156 separated as two 18-element subsets according to their complicated electronic structure and overall likeness to lanthanides and actinides, respectively. Droog Andrey (talk) 12:40, 7 March 2016 (UTC)

About the image[edit]

  • Objection to the image: the two footnote ranges are not equal in size (14 columns, 18 columns). So it is unclear (undefined) how they end up once put in the main table (above which purple columns are the 14 green columns positioned?). Whatever you want to illustrate, do not use asterisked-footnotes. Just put the elements where they should be. -DePiep (talk) 13:40, 7 March 2016 (UTC)
    • That's done on purpose. The positions of "purple" elements 121-156 has no chemical correspondence to positions of "green" elements. And that's why there shouldn't be any columns combining them. Periodic table has groups for the elements with similar structure of valence shells, but the concept of groups doesn't work for "green" and "purple" elements. We use here a concept of series: first for lanthanides, second for actinides, now third is proposed for "superactinides" 121-156. There are no any chemical reasons for vertical correlations between series of different nature. Droog Andrey (talk) 14:06, 7 March 2016 (UTC)
    Then do draw that. (First you cut and misform the Table you want to show, and then you need 100 words to explain back what you broke. Why?). -DePiep (talk) 15:51, 7 March 2016 (UTC)
    And what it does state is that all three asterisked footnotes are in one vertical column. -DePiep (talk) 15:53, 7 March 2016 (UTC)
I don't understand you. What is broken? We have a series of 4f-elements between barium and lutetium; we have a series of 5f-elements between radium and lawrencium; we also have a series of superactinides between elements 120 and 157. Of course, we could place elements 143-156 under 5f series, but there's little sense in such placement (e.g., element 146 with valence shells 6f47d28p2 should have oxidation states from +4 to +8, not a good reason to place it under uranium). We must remember than periodic table arranges elements by their chemical nature, not by formal rules. Otherwise we'd place helium above beryllium, lawrencium under thallium and so on. The current placing of elements 141-154 under f-elements is just arbitrariness.Droog Andrey (talk) 17:04, 7 March 2016 (UTC)
But that's a bit off-topic. The main question is the location of a 7d block. Fricke also suggests that element 157 should be placed into the group IIIB. What's really curious is that almost all the predicted properties (given in the article) show that element 157 is similar to Sc, Y and Lu, and the same appear through element 164 being similar to Ni, Pd, Pt. But these elements are somehow placed two more steps to the right.Droog Andrey (talk) 17:04, 7 March 2016 (UTC)
I'm talking about the image only. I call "broken" when several series are cut out of the Table and moved to below (like footnotes). Better : do not cut them out, but leave them in their place, showing one whole Table. By moving those series an extra problem is introduced (namely: how exactly are they supposed to be in their original place?). This problem is avoided when you do not move them to below. (the same problem occurs when the basic 32-column PT is redrawn into 18-column + footnotes). And I repeat: the graph now has all asterisks in one column, defining a vertical relationship (while your reply says there is no such relationship). -DePiep (talk) 17:12, 7 March 2016 (UTC)
The key is that superactinides do not follow periodic trends, we have no groups for them, so there couldn't be any "original place" for them. They are completely new phenomenon in the table, that's why this series is placed separately. All asterisks are in one column just because that "out-of-groups-rupture" appears before d-blocks every time. Again, you may expand the table, but then you will be forced to somehow align the superactinides along f-series. Since no such alignment has any chemical sense, that will be a pure arbitrariness. Droog Andrey (talk) 17:27, 7 March 2016 (UTC)
#2: does this look really better?
The expanded version, where elements 143-156 are formally assigned to 6f-series. Droog Andrey (talk) 17:56, 7 March 2016 (UTC)
Thanks. And yes, that image does look better because it shows what you want to tell here (otherwise needs 1000 words + a puzzle to solve for the reader). I note that between the two images you changed the color for 143–156 (purple to green). That's another advantage: such things are hidden or ambiguous in the disjointing Table, but are confronted in this rectangular one. (If there is a layout problem with the second image, one could consider moving only 121–142 (only) to a footnote. But it is downgrading the point you want to show). -DePiep (talk) 19:38, 7 March 2016 (UTC) (struck, see my next post. DePiep)
OK, got it. I guess there are also some technical advantages of the rectangular template for Wikipedia. Anyway, we have now more compact and simple form with straightforward increasing of atomic numbers along the table. The fact that 9s and 9p1/2 subshells participate in chemical bonding in elements 157-172 could formally be the reason to place them in period 9, but that rule doesn't work anymore because of large relativistic gap between 9s+9p1/2 and 9p3/2. Take it this way: relativistically lowered 9s+9p1/2 subshells just play the role of 8s+8p1/2 subshells by the end of the 8th period. Droog Andrey (talk) 20:00, 7 March 2016 (UTC)
#3: another try: only f-series expanded
As for the color, I'd prefer purple for all the elements from 121 through 156 to show them as just one continuous series. Maybe in the future, when more detailed calculations of chemical properties are carried out, we'll broke them apart in some way. Droog Andrey (talk) 20:08, 7 March 2016 (UTC)
──────────────────────────────────────────────────────────────────────────────────────────────────── I'm not familiar with the orbital and block issues you describe. That's why I only talk about the image. I want the image to illustrate what the text (proposed article text) says, with few or zero mental distractions. The footnote (any asterisk) is a huge mental distraction: unnecessary homework for me/Reader.
So I struck my suggestion to put any part below in a footnote (as your #3 image does). For you of course it is a very tempting shortscript (because you are inside of the issue). Please don't do that: footnoting elements does not help our Reader.
(Note to all scientists, scholars and teachers: I forbid the use of asterisk-footnoted elements in the Periodic Table. Seaborg Exception: if you have an element named after you, you are allowed to).
Do defend and push your #2 image, the very very long Table. That is what I/Reader can understand more easily (and we might look at the text even). Images #1 and #3 are IKEA-like things: compact yes, but a lot of reconstruction work to do. Compact is bad.
I see you changed color again. Color=block here, right? Now what is it? Can't have different colors for the same statement. -DePiep (talk) 21:09, 7 March 2016 (UTC)
But the current version of the article do use asterisk. What's wrong with that? A proposed version is less complicated than the current one. On the coloured blocks: as I mentioned earlier, the 121-156 block is just a continuous series of elements with 5g, 6f, 8s and 8p1/2 subshells being filled and closed; for design reasons we could still formally pull out a 6f block 143-156, but that would have little chemical sense. Droog Andrey (talk) 21:27, 7 March 2016 (UTC)
re "the current version of the article do use asterisk. What's wrong with that?"
- Sure the article should be changed, with/without your proposal here.
- This is why: the asterisked footnote requires and assumes that the Reader reconstructs the complete unmutilated Periodic table in its longest form. The Reader is loaded with the mental task to reposition those footnotes elements into the main Table (IKEA-wise), before even beginning to understand the topic. While there is no need for this: if we just show the Table in the longest form, that first huge mental action is not needed. (Think about it this way: Why would you cut & move those elements at all? You do have the full single PT at hand, don't you?).
- And this second reason: the 'compact' IKEA form hides issues into ambiguity or unclearness (giving headaches to the Reader who does try to reconstruct that longest Table). As you have shown yourself here: you had to change colors between supposedly equal versions (#1 and #2). The longest form tests you for being consistent (test failed in this). I have never seen a Periodic table asterisking elements thereby helping the Reader. Never.
-DePiep (talk) 21:57, 7 March 2016 (UTC)
(edit conflict)In image #3, you use the word "Superactinides". That is a mixup of categorisations (like, "a lot of cars are red. There are also BMWs"). Better stick with blocks only. By the way, did you consider showing this in Left Step form? -DePiep (talk) 21:31, 7 March 2016 (UTC)
#4: The expanded version without far-fetched 7f block
"Superactinides" is just the name of the block. As well as "lanthanides" is the name of 4f block, for example. BTW, look at the final expanded variant. Droog Andrey (talk) 21:38, 7 March 2016 (UTC)
Erh, "4f" is not a block. "f" is. "Lanthanides" is a 'category' in metallishness, not in blocks. -DePiep (talk) 22:02, 7 March 2016 (UTC)
  • re image #4: Great for me, because longest PT form = no asterisks :-). Cannot judge if the purple color (g-block?) below Ln/An is OK block-wise, or if it should be f-block/green. (BTW, we have a block-color set s-p-d-f-g: here, used in this article). -DePiep (talk) 22:14, 7 March 2016 (UTC)
    There's no chemical term metallishness. As for "The longest form tests you for being consistent (test failed in this)": I was just embarassed by your demand to expand the table. You know, chemical elements don't care about our understanding of their classification. The closest-to-nature form of the periodic table is the first one I proposed. Any expanding causes some sort of speculation. As for colors for blocks: there's simply no specific g-block, that's the nature of these elements. Droog Andrey (talk) 22:19, 7 March 2016 (UTC)
re "There's no chemical term metallishness". Agree, chemicists don't have a word for that. But it does exist. "Metallishness" is the categorisation we use in our Periodic table graphs background coloring, with legend (color key). My point is, that "metalishness" categorisation is not "block" categorisation. They should not be mixed up.
re "I was just embarassed" ??? How did I ask to expand the table? I only asked to change the graph, not to expanded the PT you write about here.
re "closest-to-nature form of the periodic table is the first one I proposed." - no, nature gives us a 52-column PT (as your #2 graph shows), not a "32-column plus footnotes" PT.
-DePiep (talk) 22:34, 7 March 2016 (UTC)
Nature give not any columns, just laws of physics. We use them to predict the properties of the elements and see that some of them fit a single column, while some other didn't. Elements 141-156 are those which didn't. Droog Andrey (talk) 22:50, 7 March 2016 (UTC)
Why 52 instead of 50?? A g-orbital can hold 18 electrons, and 32 + 18 is only 50. Georgia guy (talk) 22:52, 7 March 2016 (UTC)
The 5g-subshell is filled and drowned into the core together with 6f, 8s and 8p1/2 subshells, so the length of the superactinide series is 18+14+2+2 = 36 elements. Together with 18 classical groups we have 54 columns in total. Droog Andrey (talk) 23:15, 7 March 2016 (UTC)
  • TL;DR: stick to your own #2 graph. Resolve the color varying I mentioned.
Has 54 columns (not 50, not 52)
Don't use 'superactinide' as a block name
Fix the color alterations into one single statement. Add color legend (don't blame others for having to assume it is blocks)
Nature did not give us footnotes
Nature did gave us columns (groups) in the Periodic Table. That is why it is called "Periodic"
Consider showing by Janet Left Step. The quantum ordering (within blocks) seems to be relevant
And keep pushing this clarification. I like the simplicity, I'm just curious on how other editors value this.
-DePiep (talk) 23:39, 7 March 2016 (UTC)
One more time: the groups are natural, but the series 121-156 doesn't belong to any of them. BTW, why do you prefer #2 to #4? Droog Andrey (talk) 00:56, 8 March 2016 (UTC)
#4 is OK too for being the longest form (no asterisked footnotes). About groups: as you draw it (#2, #4), 143-156 are in the same group (column) as the Ln, An. -DePiep (talk) 08:20, 8 March 2016 (UTC)
By the time you are in the f-block, the groups are mostly theoretical conceits, and looking at the period left-to-right is more important. Learning about the chemistry of Cr would tell you something about Mo and W, but learning about the chemistry of Nd will not really help your understanding of U. There may be 54 columns in this table (and it's great to see that there is a source for it, because I always felt it made more sense this way), but still only 18 groups with chemical significance. Double sharp (talk) 09:16, 8 March 2016 (UTC)
So you're saying like: in the Ln, An set (14+14) column (groups) are not that meaningful. We could say "in this area of 14+14 elements the f-shell is filled", and for this topic just show two cells with Z-ranges 57-70 and 89-102 (correctly colored green for f-block). This I get and could be fine.
But the next thing we always see is that the graph is corrupted a bit more into incorrect or ambivalent showing. For example (from the regular PT), until recently this (correct) grouping also ended up hiding any statement on what is group 3. And also: how to handle Sc, Y above such a group. That's why Scerri (and I) promote: draw the PT in longest form, that forces you to think about these issues. Another example, from the source mentioned above (PT is transformed, OK). Look what they did with the footnote "*** Ultransition elements" (121-156): cut into two columns (periods), but they actually are to be read in one period. Why wrongfooting me? Next, these 46 elements are positioned, by "***", next to the 14-row actinides. But how can 36 elements fit next to 14 elements? Where is the filling space supposed to be? See, by not writing the PT in full length, these statements are hidden and ambiguous.
From the texts, I get that elements 121-156 are filling the 5g and 6f shells (with unclear border position between them). But whatever one does, that is no reason to color this whole set purple, as if being in one block (g-block). There should be a notion that f-block is being filled (green color).
All this is not helped by replacing in-table sets of elements with asterisks (even if done correctly i.e. without ambiguities), because the reader first must cut and paste that set before beginning to understand. -DePiep (talk) 10:21, 8 March 2016 (UTC)
The problem is that since the filling of the 5g and 6f orbitals overlap, it is not meaningful in any sense to declare that 142 is in the g-block and 143 is in the f-block. I could accept such an assignment only if it is stated quite clearly that this is only formal and probably has no effect on the chemistry. Double sharp (talk) 10:53, 8 March 2016 (UTC)
"But how can 36 elements fit next to 14 elements?" They don't fit and are not supposed to.
"that is no reason to color this whole set purple" The reason is that these elements 121-156 really form a new series.Droog Andrey (talk) 11:58, 8 March 2016 (UTC)
"They don't fit and are not supposed to" - but the table says they should be next to each other. That is the essence of using the "***" placeholder: there is no place for all 36 elements.
"121-156 really form a new series" - what is 'series'? not a block? not part of a period? If they are unrelated to anything else in the PT, I think they don't belong in there at all. But actually, I think they are just the new g-block and a third period of the f-block. -DePiep (talk) 12:09, 8 March 2016 (UTC)
They are a part of 8th period. They are unrelated to other sets of elements. They belong to the PT. Their nature is irrelevant to what we think. Droog Andrey (talk) 13:02, 8 March 2016 (UTC)
I'll give this a rest and hope you two can make a great immprovement to the article with this topic. -DePiep (talk) 18:24, 8 March 2016 (UTC)

Location of the 6f series[edit]

According to predictions, the whole set of the elements 121-156 has their 6f subshell available for chemical bonding, and it is quite difficult to exactly locate the 6f series. But we may look at the earlier periods: 5d electrons appear in La and Ce, way before the 5d series; 6d subshell is populated in many actinides; 7p electron is active in lawrencium before p-block. So we see that p, d and f-blocks correspond to the valence subshells with highest angular momentum, with possible exceptions for Zn and Cd. Indeed: Ac and Th use their 5f, 6d, 7s and probably 7p subshells, which make them members of f-block, while Lr use only 6d, 7s and 7p and is a member of d-block.
Looking at the configurations of elements 121-172 predicted by various authors, we may notice which subshells are probably valence either as highest occupied (HO) or as lowest unoccupied (LU):

  • elements 121-142 use 5g, 6f, 7d, 8s, 8p1/2 subshells as HO or LU, so they might belong to g-block;
  • elements 143-156 use 6f, 7d, 8p1/2 subshells as HO and maybe 9s as LU, so they might belong to f-block;
  • elements 157-166 use 7d and 9s subshells as HO and 9p1/2+8p3/2 as LU, so they might belong to d-block;
  • elements 167-172 use 9s and 9p1/2+8p3/2 as HO, so they might belong to p-block.

The most arguable thing is the precision of these bounds. 7d-series, from 157 to 166, is discussed in the previous section; let's now concentrate on the bounds for 6f series.

Pekka Pyykkö's computations show that element 142 is the last one where 5g and 8s subshells are still open for chemical bonding. Although the neutral atoms of elements 143 and 144 has probably still unfinished 5g-subshell, it become 5g18 when atom is positively ionized (the reason was mentioned in the previous section: subshells with higher angular momentum are drowned deeper because of less screening). On the other hand, positive charge is the only way to reach 5g orbitals for (at least indirect) chemical bonding because of their small size. Therefore, element 142 is a good candidate for the end of g-block.
So, 6f series is probably started at element 143 since its 6f subshell has the highest angular momentum among valence subshells 6f, 7d and 8p1/2. As for the right end of the 6f series, most of the authors agree that 6f become filled near element 156. Pekka Pyykkö shows that triple cation of element 155 has 6f14 and still may be chemically ionized further (the calculated ionization potential for Upp3+ is higher than for Tb3+, but lower than for Dy3+). Other authors predict a bit higher energy of 6f subshell in the vicinity of Z=156, but all of them agree that for Z=158 the 6f subshell is buried deep down together with 8p1/2.
Taking all of this into account, it might be possible to formally assign:

  • elements 121-142 to g-block (although 5g is empty for a few first elements, it is used as lowest unoccupied subshell, just like 5f for Ac and Th);
  • elements 143-156 to f-block (although we need more accurate predictions to see a tight deadline where 5g subshell becomes inactive);
  • elements 157-166 to d-block (although 7d subshell is probably inactive in element 166, that's the very case for zinc (3d) and cadmium (4d), so the analogy resists);
  • elements 167-172 to p-block (although there's no pure 8p subshell, a hybrid 9p1/2+8p3/2 will go well for 8th period).

But then we should certainly make a warning that this is only a rough pattern, while the real chemistry of these elements is far deeper, and now we have no calculations precise enough to make more detailed arrangement of elements in 8th period. Droog Andrey (talk) 15:17, 8 March 2016 (UTC)

That's how it will look like.
I support this. You make a lot of sense and argue based on many reliable sources. (I'll need to rewrite the part about 165 and 166 to make it clear that they are probably going to be closer to IB and IIB than to IA and IIA, though that does not, of course, bar them from having some characteristics of the latter.) Like you, I don't think we can say any more till more theoretical studies appear, or we synthesise all the period 8 elements till 172 (and I am very doubtful that either of us will live to see that). Double sharp (talk) 15:33, 8 March 2016 (UTC)
(I really like this development. Looks great). -DePiep (talk) 20:51, 11 March 2016 (UTC)
I can't see the far left of that image; there's no scroll option. This image is just like simple extrapolation except that the g-block has 22 elements instead of 18. Any corrections to what I'm saying?? Do 4 of the 22 elements in the 121-142 interval belong to a special block?? Georgia guy (talk) 21:03, 11 March 2016 (UTC)
(Just click the image, and you arrive at the image view for a complete viewing). It's not a simple extrapolation. It is a careful and helpful representation of the sources. It really helps the average Reader (trust me). -DePiep (talk) 21:25, 11 March 2016 (UTC)
The main comment I have is that I support that, in an appropriate position, this article needs an image of the periodic table made by simply extrapolating the periodic table. Yes, the article has a message saying "Although simple extrapolation..." for clarification on what it would be. Georgia guy (talk) 21:32, 11 March 2016 (UTC)
I don't get what you mean, because I only can talk about the graphics (including the horizontal scrolling option; it'll be allright in any article for sure). For the textuals like Although simple extrapolation... (sure that is a bad article approach!), I leave that to other editors here on this talkpage. -DePiep (talk) 22:07, 11 March 2016 (UTC)
(I'm very, very interested where this conversation between Droog Andrey and Double sharp leads to. Will be a great article improvement, also into Readers' like me understanding (that is: clarifying). Now back to the main topic.) -DePiep (talk) 23:17, 11 March 2016 (UTC)
A periodic table by "simple extrapolation" would look exactly the same, but would end the g-block at 138 instead of 142. (So, for example, 168 would be under 118 instead of 172.) Double sharp (talk) 09:36, 12 March 2016 (UTC)
Let's make a difference between "simple extrapolation" and "extrapolation of Madelung's rule". The variant with element 168 in the VIIIA group is just a meaningless venture to pull the Madelung's rule beyond 7th period where it doesn't work because of progressive relativistic effects. The variant I proposed is indeed a simple extrapolation, but it is overall supported by rough quantum-chemical calculations. To ensure any more detailed arrangement of the elements (say, to prove some explicit bounds on some special series and so on), we should wait for some deep calculations of atomic and molecular species with at least MRCI level of theory with high-order relativistic hamiltonian. Droog Andrey (talk) 23:45, 13 March 2016 (UTC)
You're right, of course, but your extrapolation is not really conceptually simple. It looks simple, but you can only get to it via relativity, so perhaps it could be stated to be based on a more detailed, relativistic look at the situation. Meanwhile, we could clarify the wrongness of the Aufbau extrapolation by calling it a naïve extrapolation. Double sharp (talk) 15:20, 14 March 2016 (UTC)
Sounds good to me. Droog Andrey (talk) 20:12, 14 March 2016 (UTC)

I reread Fricke's paper, and even he (what with his placement of 164 under Hg and Cn) says it is most analogous to group VIII (= 10). In fact, he writes in Table 6 that 157 should be most similar to group IIIB, 158 to group IVB, and so on. As for 165 and 166, Fricke puts them in IA and IIA, citing predicted ionisation energies which fit the trend in these groups better than those in IB and IIB. But he also admits that 7d will be active chemically, which is unlike the behaviour of IA and IIA, because it is easier to penetrate a filled d10 shell than a filled p6 shell. Since chemical properties form the basis of this whole extrapolation, I think we really should change this to the format proposed above.

Double sharp (talk) 14:50, 2 August 2016 (UTC)

P.S. Regarding 167–171; I cannot imagine an element with such density being a nonmetal or metalloid, and I only mark 171 as such for its chemistry. Double sharp (talk) 15:02, 2 August 2016 (UTC)
That looks very good. Droog Andrey (talk) 21:27, 13 September 2016 (UTC)

configurations of 121 and 122 ions[edit]

121: [118]8s, [118]8s2, [118]8s28p

122: [118]8s, [118]8s2, [118]8s27d, [118]8s27d8p Double sharp (talk) 15:46, 14 July 2016 (UTC)

Naming suggestions:[edit]

Superactinides could be called Unbiunides since the first 'superactinide' is called Unbiunium and we can change it once we discover it and give it a name. Unsepttrides would be the next set of superactinides since Unsepttrium is the first of such section.

Lanthanides = 15 Actinides = 15 Superactinides = 14 + 20 = 34 Another set = 34 More sets would go by this pattern: 13 + 25 = 38, 38, 42, 42, 46, 46, 50, 50, 54, 54, etc... each set being named after the first element in each set. -- (talk) 13:33, 18 July 2016 (UTC)

Predicting to Group 13[edit]

I have made a periodic table predicting elements to Group 13. Link: -- (talk) 16:00, 25 July 2016 (UTC)

I doubt that elements with large atomic numbers will follow simple extrapolation. Georgia guy (talk) 18:56, 25 July 2016 (UTC)

"or could even have completely decayed by now after having caused the radiation damage long ago"[edit]

sorry, but this is not idiomatic English (and borderline incomprehensible). (talk) 09:19, 23 August 2016 (UTC)

Really? I understand it quite simply as stating the possibility that these superheavies were around long ago and caused radiation damage as they decayed, but are gone. Nevertheless I have cut it into two sentences to make it a little more obvious: "The possible extent of primordial superheavy elements on Earth today is uncertain. Even if they are confirmed to have caused the radiation damage long ago, they might now have decayed to mere traces, or even be completely gone." Double sharp (talk) 15:19, 23 August 2016 (UTC)

in popular culture[edit]

So there is one story mentioning element 126. What's the significance? Double sharp (talk) 15:19, 23 August 2016 (UTC)

Super extended periodic table[edit]

If we added 2 rows to our periodic table we have one with an H block, that goes to 362.
If we added 2 more, it would have an I block, that would make it go to 558. I guess that we could call this the super extended periodic table.

If we keep adding 2 more rows each time, we get this pattern:

Period # Final
Element #
15 814 J
17 1,138 K
19 1,538 L
21 2,022 M
23 2,598 N
25 3,274 O
27 4,058 Q
29 4,958 R
31 5,982 T
33 7,138 U
35 8,434 V
37 9,878 W
39 11,478 X
41  ? Y
43  ? Z
45  ? A
47  ? B
49  ? C
51  ? E

The final block of the periodic table with 51 periods is the E block.
We ran out of letters.
As you can see here, after 39 periods, there are over 800 groups, which looks like there's too many groups in the table.
After 42 periods, it looks like there's too many periods in the table! (talk) 21:18, 8 September 2016 (UTC)

The problem with that is that the periodic table would have ended at Z = 173... Double sharp (talk) 04:58, 13 September 2016 (UTC)
The periodic table actually goes to Z = 218 (talk) 14:06, 13 September 2016 (UTC)