[Pw_forum] memory allocation failed

[Paolo Giannozzi]

On Monday 06 March 2006 11:23, gmonaco at unisa.it wrote:

> I have tried several times to make phonon calculations on a large cell
> While the program terminated using some pseudopotentials, upon a
> change of basis a memory allocation error was obtained [..]
> The working pseudopotentials are:
>  C 12.00  C.blyp-mt.UPF
>  H  1.00  H.blyp-vbc.UPF

these are norm-conserving ...

> The problematic pseudopotentials are:
>  C 12.00  C.pz-rrkjus.UPF
>  H  1.00  H.pz-rrkjus.UPF

and these are ultrasoft PP's. In the latter case the phonon code requires
more memory and it is not really optimized for large cells. In the case of 
C and H, you do not gain much anyway from USPP in a  phonon calculation.
You gain if you have transition metals, typically, but if you want to perform
phonon calculations in large cells, you have to work on the code to make
it less memory-hungry, I think.

Paolo

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