[Pw_forum] stress in CP vs PW, previously no subject

[Paolo Giannozzi]

On Thursday 16 February 2006 20:51, Eduardo Ariel Menendez P wrote:

> Then I have a significant difference in the pressure of 29 kbar 
> with pw vs -100 GPa with CP. 

you are not the first who claims that CP and PW yield different results
for the same system. I have heard many such claims in the past, and
almost all of them turned out to be fake: the comparison was not correct.

You will have better chances to be taken seriously :-) if you find a
simpler system, calculated with as little options as possible, showing 
a difference. If there is really one, it will show up in a simple system 
as well.

Paolo

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