[Pw_forum] Is the Graphite surface flat ?

[Nicola Marzari]

Masoud Nahali wrote:
>
> *to D. C. Andera: *this pseudopotential reproduces the experimental 
> cell parameter of the bulk correctly and exactly. the predicted cell 
> parameter in z-direction (c) by the other pseudopotentials is not so 
> exact and sometimes, a difference about 1 angstrom compared to 
> experimental value appears.


Dear Masoud,

Andrea Dal Corso has told you that the pseudopotential you are
using is not to be used for standard simulations (it has an artificial
hole in the core, for spectroscopic calculation).

It seemed a perfect, and perfectly clear, answer. Change the 
pseudopotential,
and repeat the calculations. Compare yourself e.g. with Mounet et al,
Phys Rev B (2005) - use the same pseudo, and see if you get *exactly* the
same results.

                nicola



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