[Wien] Sum of PDOSes doesn't give total DOS

[David Holec]

Good morning all,

this is just to finish this thread. I have found answers to my questions 
here:

http://zeus.theochem.tuwien.ac.at/pipermail/wien/2007-January/008616.html

David

David Holec wrote:
> Thanks for the reply. Am I able to dig this out somehow? Or is the 
> interstitial basically everything else?
> 
>   DOS_interstitial = DOS_total - sum_{all atoms} PDOS_{atom}_total
> 
> Is this the case? Then, would it make any sense to interprete whatever I 
> get from tetra as that portion of density of states that can be 
> unambiguously identified with a particular atom & orbit?
> 
> David
> 
> Cormac McGuinness wrote:
>> There is also the interstitial DOS
>>
>> Cormac
>>
>> - Sorry - I should reply to the list - will send anyway
>>
>>
>> On Fri, 2008-05-02 at 15:25 +0100, David Holec wrote:
>>> Dear Wien2k users & developers,
>>>
>>> I'm getting a bit puzzled by following problem: when I calculate 
>>> total DOS of a system using tetra, and at the same time calculate 
>>> PDOS of that system, the sum of DOSes does not add up to total DOS.
>>>
>>> Let me be a bit more specific: I have a 4 atomic unit cell of AlN, 2 
>>> atoms being Al and two N. My assumption would be that when I use 
>>> following int-file
>>>
>>> Title
>>>   -1.50 0.002 2.500 0.003   EMIN, DE, EMAX, Gauss-broadening(>de)
>>>      11                     NUMBER OF DOS-CASES specified below
>>>      0    1   total         atom, case=column in qtl-header, label
>>>      1    1   Atom1 tot
>>>      1    2   Atom1 s
>>>      1    3   Atom1 p
>>>      1    4   Atom1 pz
>>>      1    5   Atom1 px+py
>>>      2    1   Atom1 tot
>>>      2    2   Atom1 s
>>>      2    3   Atom1 p
>>>      2    4   Atom1 pz
>>>      2    5   Atom1 px+py
>>>
>>> then it would hold e.g.:
>>>
>>>    Atom1 tot + Atom2 tot = total
>>>
>>> or:
>>>
>>>    Atom1 s + Atom1 p = Atom1 tot
>>>
>>> When I integrate the total DOS (column 2 of the output corresponding 
>>> to the above tetra input) over -20eV to 0eV, I got 16.004e which is 
>>> very close to 16e I am expecting in the in this region (I am 
>>> basically missing 4*2 1s electrons which are deeper than my energy 
>>> window). But the same integral for Atom1 tot (column 3 in the output) 
>>> gives 1.4285e whereas for Atom2 tot (column 8 in the output) it gives 
>>> 8.5117e. Their sum is 9.9404e...
>>>
>>> I assume it is tricky to try to distinguish which electron belongs to 
>>> which atom in solid state but still I would expect that the sum of 
>>> these two would be give the total DOS.
>>>
>>> Could any help me either how to get out of this (can I simply 
>>> renormalise the PDOSes in order to get correct number of electrons?) 
>>> or tell me where my thinking goes wrong?
>>>
>>> Many thanks in advance,
>>> David
>>> _______________________________________________
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>>> Wien at zeus.theochem.tuwien.ac.at
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>>>
>