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I was recently reading this article along with electron shell/sub shell articles specifically for the purpose of learning about alternative representations.

My real interest is in alternative representations of the 4 cube/hyper cube/Tesseract.

All I can really find are the commonly accepted representation as seen here: https://en.m.wikipedia.org/wiki/Tesseract

And Hinton’s colored cubes: https://higherspace.wordpress.com/tag/hintons-cubes/

If anyone can link any other alternatives.

Another 'fun' thing to go through is the naming of the various elements, and some of the elements that were named, but turned out to be other elements already (Canadium, for example).

Tom Scott has a great video on how Ytterby, Sweden managed to get four (!) elements named after it : https://www.youtube.com/watch?v=l6lGe5jgZgI

More on the naming of the elements here:

https://www.carolina.com/teacher-resources/Interactive/namin...

https://books.google.com/books?id=Ck9jBAAAQBAJ&pg=PA223&lpg=...

> how Ytterby, Sweden managed to get four (!) elements named after it

Those four elements are yttrium, erbium, terbium, and ytterbium. The short answer as to how a small village could get so many elements named after it is that rare earth elements are so difficult to separate from each other. So the compound that was thought to be yttrium was actually a mixture of several of them. (Cerium provided the other group of rare earths--this eventually resulted in didymium, which was considered an element for a few decades until people realized it was actually a mixture of praseodymium and neodymium). Terbium and erbium were the second and third elements found from yttrium.

What a coincidence, I stumbled upon this page very recently!

I like the left-step one actually, it makes so much sense, more than the standard one in fact I would say (but I'm not a chemist though)

The left-step one actually disguises a few important facts from the normal periodic table.

The obvious one is that He (which is only a full s shell) is far more similar to elements with full p shells than those with only a full s shell. In terms of bonding, the outermost s and p shell influences bonding the most. He, who has no p shell, acts far more like an element that has a full p shell than an element that only has a full s shell and an empty p shell because of the influence of the p shell on bonding, so you do want to stick He in the same group as Ne, Ar, Kr, Xe, and Rn.

The other thing that is tricky is where the f block starts to integrate in the table. The f shell of electrons is far less involved in bonding and observable effects than the d shell is. Furthermore, even the basic electron configuration breaks down because the f and d blocks are so similar in energy. La and Ac both fill their first d electron before the f electron, and several actinides actually retain this single outermost d electron rather than dumping everything in the f block. There is some dispute as to whether or not you should put La/Ac in the d block, or Lu/Lr in the d block, or instead put the entire La-Lu/Ac-Lr block in that one-element hole (this is perhaps one of the reasons why people like using the short form a lot--you can be somewhat vague here).

I haven't thought about chemistry in a while, but He as an alkaline earth metal just makes me laugh.

(I have seen layouts where H is above F, though, and I can get behind that...)

>> He, who has no p shell, acts far more like an ...

Sorry (downvotes...incoming), but this sounds the great start to a double entendre.

I always found it strange that the standard view usually depicts Lanthanum + Actinium on the main block and Lutetium + Lawrencium on the auxiliary. I suppose historically it makes sense that valence was the motivating factor, but at my (totally layperson at this point) glance, the pedagogy seems like it would be simpler to just adopt a more electron-orbital-focused design like the "left step" one.

In any case, it's not like anyone should really be looking at the table placement of an element say to themselves "ah yes now I know everything about how this behaves"; the exceptions are basically an intractable necessity in chemistry.

Lanthanum + Actinium actually do have the electron configuration you'd expect for a leftmost d block element--their third electron goes into the d block instead of the f block.

In practice, the period 6 and 7 elements have quite a few violations of the Afbau principle, and some predictions of period 8 predict some truly anomalous things for electron configuration (e.g., let's start filling up the 9s/p shells before the 8p shell is finished).