[Pw_forum] Pressure calculations at gamma (version espresso 2.1.4)

[Paolo Giannozzi]

On Friday 27 January 2006 16:42, merlin.meheut at lmcp.jussieu.fr wrote:

> Nevertheless, I am surprized that the pressure calculated with k = 0, 
> with the espresso 2.1.4 version (-20 kbars), is such different from the
> pressure calculated: [...]
> - at k different from zero (I tried k=0.5 0.5 0.5 , and k=0.0, 0.0, 0.5),
> with the  espresso 2.1.4.

the correct comparison is between the pressure calculated using
   K_POINTS (Gamma)
(using gamma-specific algorithms) and
   K_POINTS
 1
 0.0 0.0 0.0 1.0
(not using them). There was in some version a potential problem 
(an unitialized variable) with stress calculation that should have been
fixed by now.

> My input files are partially contained in a precedent post.

there is no indication of the pseudopotentials used, so your input
is useless 

P.

-- 
Paolo Giannozzi             e-mail:  giannozz at nest.sns.it
Scuola Normale Superiore    Phone:   +39/050-509876, Fax:-563513 
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