Well ...
I dont have much information about your system ... Is it a molecule? Or a
polymer maybe?
Anyway ... I dont know if it makes much sense calculating organic solids
with GGA. The solid state in such materials is highly dependent on
dispersion interactions like van der walls and london forces, which are not
described by GGA. Thus, I would not be suprised with large cell parameters
in this cases. Some guys I know correct it by ading an empirical
Lenard-Jones like potential in the system ... but ...it is something ad
hoc.
Cheers
Ney
On Tue, Jun 16, 2009 at 10:40 AM, Sridhar Neelamraju
neelamraju.srid...@gmail.com wrote:
I imagine siesta uses primitive (Wigner-Seitz)cell parameters whereas
experimentalists prefer crystallographic units. Could someone else confirm
the same please?
2009/6/16 samtong zjx...@gmail.com
Deal all,
Attached is the .fdf file.
The Pseudopotencial and basis sets of C, H, O, N, S in the system are
downloaded from siesta website. But the calculated lattice parameters are
almost doubled than experimental value. Could anyone tell me where i am
wrong? Thank u very much.
Chales
--
Sridhar Neelamraju
PhD Student, Jansen Group
Max-Planck-Institute for Solid State Chemistry
Stuttgart, Germany - 70569
E-mail:s.neelamr...@fkf.mpg.de e-mail%3as.neelamr...@fkf.mpg.de
Landline: (+49)0711-12164749
Mobile: (+49) 0176-70128213
