[Pw_forum] Cu US PP with PBE exchange

[Paolo Giannozzi]

On Friday 01 October 2004 19:07, Hong, SamPyo wrote:

> I tried several Ecut values and realized at least 30 Ryd is needed

there are two cutoffs for ultrasoft PP's, one for the expansion of the
Kohn-Sham orbitals and one for the expansion of the charge density. 
By default, and in norm-conserving PP's, the latter is four times the 
former, but in ultrasoft PP's it is often convenient to use a cutoff 
for the charge  density that is larger than this

Paolo

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