[Pw_forum] General pseudopotential generation questions (using ld1)

[Paolo Giannozzi]

On Oct 2, 2007, at 23:28 , Tyler Grassman wrote:

> With Ge, however, the results *is* weird.  The potentials produced  
> with
> lloc=-1 (4s2 4p2, no semicore d) give a lattice parameter that is  
> actually
> smaller than experimental (10.60 vs 10.69 Bohr, which definitely seems
> funny for a GGA calc), while potentials using 4s2 4p2 4d-1 (lloc=2)  
> and
> 4s2 4p2 4d-1 4f-1 (lloc=3), give values larger than experimental,  
> as would
> be expected.  The lloc=3 case, which is the same used in the VASP
> US-PPs, gives the best results (10.91 Bohr).

in diamond and zincblende semiconductors, the lattice parameter
depends a lot on the quality of the d-channel pseudopotential

P.
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Paolo Giannozzi, Dept of Physics, University of Udine
via delle Scienze 208, 33100 Udine, Italy
Phone +39-0432-558216, fax +39-0432-558222