Why vary from IUPAC for lanthanoids and actinoids?
Webelements provides a valuable service and I'd like to help make it better.
IUPAC's "Nomenclature of Inorganic Chemistry" (1990) redbook p 43 I-3.8.2 calls Lu a lanthanoid and Lr an actinoid. The provisional redbook about to come out will say the same thing. Webelements own entry for Lu essentially says it's isolated from other lanthanoids. So why have a row labelled "lanthanoids" that are a different color and in a different location than Lu? Lu is a "d-block lanthanoid" in a similar manner (in terms of nomenclature at least) to He being an "s-block noble gas," yes?
I know I'm supposed to refer to J. Chem Ed. (1982) 59 634-636 by W.B. Jensen and I'm in the library reading it now. It presents great evidence to support its conclusion: "All of these properties unanimously favor the placement of lutetium and lawrencium, rather than lanthanum and actinum, in group IIIB [below Y]" and I agree. If I were forced to either place La/Ac below Y or Lu/Lr there, I'd pick Lu/Lr like you have done, but the 18-column table that IUPAC uses puts both there along with everything in between because they're all called lanthanoids. OK...of course, the 32-column IUPAC table makes the most sense, but we're not talking about the 32-column table.
Now make fun of me, call me obsessive and a pedant, talk about it all being semantics, imply I'm supposed to dislike IUPAC for some reason, say I should get back to work doing something to make money or help the world, and you'll be right on all counts. Then please think of countless classrooms around the world where a table that makes it plain that Lu is a lanthanoid differs from your table and think of countless children and teachers who are stumped--like me--about why information on the internet has to be so inconsistent with accepted practice.