The ABINIT Users Mailing List ( CLOSED )

[verstraete@pcpm.ucl.ac.be]

Hello,

you've used the cold smearing scheme for the occupation of you electronic
levels. This is very good for the energy etc... but it has an unphysical
smearing function, in that it goes negative (and the occupation goes above
2). For the DOS calculation, by default, ABINIT uses the same smearing
delta as the occupation one. This is why you get the negative values.
See Nicola Marzari's PhD thesis for a very clear explanation of his cold 
smearing scheme.

Either re-run the DOS calculation from the same wavefunctions, but with
occopt 7 (gaussian smearing), or, starting with the next version of abinit
you can use prtdos 2 to employ the tetrahedron method for the DOS. There
is a bug in the present version: the results are correct, but you can get
a "divide by zero". The bug is fixed and should be eliminated for 4.0.3 
(Xavier?)

Matthieu

-- 
===================================================================
Matthieu Verstraete               mailto:verstraete@pcpm.ucl.ac.be 
PCPM, Boltzmann, pl. Croix du Sud, 1            tel: 010/ 47 86 81
B-1348 Louvain-la-Neuve  Belgium                fax: 010/ 47 34 52