The ABINIT Users Mailing List ( CLOSED )

[Vincenzo Fiorentini <vincenzo.fiorentini@dsf.unica.it>]

Dear all, on the 3d valence electrons issue
for GaN (4d for In) I have personally concluded,
after a great deal of experiments [started with
PRB 47, 13353 (93) ;)] by myself and valuable
coworkers including e.g. F. Bernardini, that to stay
within reasonable cutoff limits and still get high quality
results, ultrasofts are needed. We have been using various
uspp versions since 1993 in the nitrides trade, with some
success. PAW, obviously, is also an answer (coming up in
abinit, I understand). PAW and LDA (VASP) gives GaN bulk
l.p.'s within 0.5 % of expt.

This notwithstanding, you can get around it with ncpp,
occasionally even with non-linear corrections. This is
testified by the excellent past and current work by
Joerg Neugebauer, now at FHI Berlin. He is the one who
is in the know about nitrides with ncpp's, and he may not
be on this forum...

best, Vincenzo




--


    Prof. Dr. Vincenzo Fiorentini

    vincenzo.fiorentini@dsf.unica.it
    INFM - Dipartimento di Fisica
    Universita' di Cagliari
    Cittadella Universitaria
    S.P. Monserrato-Sestu Km 0.700
    I-09042 Monserrato (CA), Italy
    tel +39 070 6754912
    fax +39 070 510171