[Pw_forum] phonon at Gamma point

[Paolo Giannozzi]

On Sunday 20 August 2006 00:36, Yansun Yao wrote:

>       Other than the internal coordinates, did you optimize the unit cell?

while a good thing in general, optimization of the unit cell is not needed
to have positive phonon frequencies at q=0, as long as atomic positions
are in equilibrium

Paolo
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Paolo Giannozzi             e-mail:  giannozz at nest.sns.it
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