Lutetium and Lawrencium

I hopping someone could clarify why Lu and Lr are not considered part of the lanthanoid and actinoids series perspectively, as listed in my old chemistry book.Also now La and Ac are considered lanthanoids and actinoids? I will be attending Sac State this fall, majoring in chemistry, and I would like to be up to date on my periodic table. Thanks for the help.

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A bit of a toutchy subject, I gather, and I may be totally wrong. But I think they are not considered as they have a filled f shell, and a single d electron, placing them in the d block.

But the same can be said for La and Ac (having a single d electron, and not even a single f electron).

So I imagine there are some slightly more technical arguments over this subject, relating to QM?

Hopefully somebody more knowledgeable will post in reply..

Personally I suspect it's just the sort of idle nonsense that quangos think up when they have committee meetings in the Bahamas lol

Send 'em back to the lab to get on with doing sthg more useful

Re: Lutetium and Lawrencium

[quote="the squid"]I hopping someone could clarify why Lu and Lr are not considered part of the lanthanoid and actinoids series perspectively, as listed in my old chemistry book.Also now La and Ac are considered lanthanoids and actinoids? I will be attending Sac State this fall, majoring in chemistry, and I would like to be up to date on my periodic table. Thanks for the help.[/quote]

Periodic table organisation: for a justification of the positions of the elements La, Ac, Lu, and Lr in the WebElements periodic table see W.B. Jensen,

[quote="feline1"]Personally I suspect it's just the sort of idle nonsense that quangos think up when they have committee meetings in the Bahamas :lol:
[/quote]

While IUPAC are easy to snipe at (as they largely can't answer back), and I've done my share of that, their position here is pretty good. See the Appendix in the the Red Book (IUPACs Nomenclature of Inorganic Chemistry), and in particular Table A-III on page 283.

Lutetium and Lawrencium are not in the rare earth is because of the s2, f14, d10, p6 sequence.
Before, people thought it was s1, p1, d1, f14, d9, p6. That's the problem.

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