[Pw_forum] dos

[Stefano Baroni]

On May 8, 2009, at 5:55 PM, Axel Kohlmeyer wrote:

> particularly the notion of anti-bonding MOs worries me. those tend
> to have restricted meaning in pseudopotential DFT calculations to
> begin with.

well, it depends. I guess that the antibonding combination of atomic  
arbitals that ar occupied in the atomic ground state is not any worse  
than the lbonding combination ... surely, linear combinations of  
atomic orbitals that are not occupied in the atomic ground state  
begome less and less meaningful as the enrgy grows large.

> in any case one has to be well aware of the fact, that the molecular
> wavefunction that the DOS are projected on is to a significant degree
> arbitrarily chosen and it is based on an assumption of non-interacting
> molecules.

not differently of how atomic pdos are based on the assumption of non- 
interacting atoms. actually, it is preciseley for assessing the  
deviation from a non-interacting atom situation that the atomic pdos  
are most useful ...

creers - S.



---
Stefano Baroni - SISSA  &  DEMOCRITOS National Simulation Center -  
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