[Pw_forum] Implementation of DOS in real space

[Guido Fratesi]

Dear Q-E (especially pwscf) developers,

I was needing an evaluation of the density of states (DOS) as function of 
energy, integrated in a volume, rather than projected on the atomic 
orbitals as done by projwfc.x. The purpose was to highlight electronic 
states which have significant weight right outside a surface.

I have implemented its calculation, for the norm-conserving part of the 
charge, in projwfc.x (really, I have re-adapted to the CVS version my 
previous implementation, with refence to previous discussion on this 
forum:
http://www.democritos.it/pipermail/pw_forum/2008-September/010005.html ).

The use of the norm-conserving part only was because the augmentation 
part does not contribute far from the atoms (the same is done when 
plotting STM images by pp.x). Conversely, near the atoms, the projection 
on atomic orbitals as currently implemented is probably more suited.

It would be nice, in my opinion, to have this feature embedded in the 
espresso release. Yet I don't know if this opinion is shared among the 
users/developers, and the details of its best incorporation. I can provide 
the source code (only projwfc.f90 was modified) and a working example if 
that is of common interest. Maybe, the easiest way is that I get contacted 
by some of the developers for the details, directly or via the forum. 
Please let me know.

Best regards,
Guido Fratesi

-- 
Guido Fratesi

Dipartimento di Scienza dei Materiali
Universita` degli Studi di Milano-Bicocca