[Pw_forum] About LDA and GGA

[Lex Kemper]

Hi Bipul,

This sort of question is hard to answer without more specifics. People 
who have worked on certain materials will be able to tell you what 
LDA/GGA think about the lattice constants, but AFAIK the 
over/underestimation by LDA/GGA are trends, not certainties.

Lex Kemper
Department of Physics
University of Florida

Bipul Rakshit wrote:
> Dear PWSCF users,
> Generally LDA underestimate the lattice constant and GGA overestimate
> it. But is it possible that for some materials, LDA also overestimate
> the lattice constants, when compared with experimental value?
> 
> regards
>