Töilet Plünger
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Why is lutetium in the f-block and lanthanum in the d-block?
As far as I know they are both in the wrong places. Lanthanum does have the [Xe]5d1 configuration, but on the basis of properties and the
unfilled f-shell, I would expect it to be a f-block element. If not, then cerium, gadolinium and terbium should be d-block elements because of the d
electrons they contain.
Lutetium, on the other hand, is obviously a d-block element: it has a 4f145d1 configuration, with a filled f shell. Its
properties resemble scandium and yttrium more closely than lanthanum's. I wouldn't even call lutetium a lanthanide - I'd call it a transition metal,
as with scandium and yttrium.
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DraconicAcid
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Lanthanum doesn't have any f-electrons, and has no more reason to be considered an f-block element than calcium should be considered a transition
metal.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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blogfast25
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Quote: Originally posted by Töilet Plünger  | | Lutetium, on the other hand, is obviously a d-block element: it has a 4f145d1 configuration, with a filled f shell. Its
properties resemble scandium and yttrium more closely than lanthanum's. I wouldn't even call lutetium a lanthanide - I'd call it a transition metal,
as with scandium and yttrium. |
By that reasoning zinc couldn't be a d-block element either, because its d orbital is full. It doesn't work like that: f-block elements are considered
to be that because the orbital filling proceeds in 4f. It just so happens that with Lu the 4f orbital is full because it's the last in the 4f series.
Going by properties is very old fashioned: all elements show resemblances and differences and we tend to project simple rules onto them. Electronic
configuration is a better way of grouping them.
'Transition metal' is an old and clumsy term. Transition from what to what, exactly?
Nor can they really be 'in the wrong place', as place is determined by Z.
Don't fight windmills. 
[Edited on 7-4-2014 by blogfast25]
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Töilet Plünger
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When I was talking about how lutetium is a transition metal, I meant that its f shell is filled and its d shell is unfilled. By that definition
ytterbium would also be a transition metal, not a lanthanide.
The position is determined by the lowest unfilled orbital. In the case of lanthanum this is the 4f orbital and for lutetium this is 5d. This doesn't
count exceptions produced by unfilled s shells, such as chromium and copper.
(Note: the s-block should technically be adjacent to the noble gases and helium should be on top of beryllium if you want to have a true periodic
table of electron configurations.)
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blogfast25
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Like I said, I think you're being uncharacteristically quixotic.
H and He are now considered 'special cases' and placed accordingly, in many of the latest versions.
Why should the s-block 'technically' be adjacent to the noble gases? What would be achieved by that? Ar is quite logically adjacent to Cl because its
Z is one higher and because the 3p orbital is full at Ar.
Little is achieved by your proposed rearrangements, as far as I can see. I would refrain from that project called 'letter to IUPAC', if I were you.
[Edited on 8-4-2014 by blogfast25]
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Brain&Force
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A left step periodic table shows the filling order of the elements.
At the end of the day, simulating atoms doesn't beat working with the real things...
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Töilet Plünger
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Most newer periodic tables don't have this odd layout, and instead place lutetium in the d-block and lanthanum in the f-block. It's just that one of
my chemistry teachers and I were confused on this point because of the old periodic table.
By the way, if you think I'm tilting at windmills, please click on the link in my signature. 
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blogfast25
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That kind of thing is never going to fit on my wall! Sir, if this thing ever get proposed, I will have to voice my opposition in the loudest of
fashions!
I had an inkling your 'lutetium folly' would find its origins in this stepped heresy! Pistols or daggers, your choice...
Very funny, your pi thing...
[Edited on 8-4-2014 by blogfast25]
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aga
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The PT is basically a fashion item.
As understanding progresses, each element may well occupy it's own Cult, and suggesting it has a place in a table could well be called Heresy.
I will side with the 1s 2py excited hybrid faction, unless the dislocation splinter group gains momentum.
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blogfast25
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To some perhaps. But it's also crowning proof that the chemistry of the elements is organised by quantum mechanics, a very important development in
the history of chemistry, perhaps THE most important one.
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