[Pw_forum] different born effective charges

[Lorenzo Paulatto]

On Wednesday, 5 April 2017 12:45:05 CEST VineetKumar Pandey wrote:
> in the output file of ph.x executable, there is given effective charges
> calculated by different methods (1. through force per unit electric field,
> 2. through polarisation per unit cell ). and both are different. which one
> is reasonably good?

One is as good as the other, if you need more precision you have to increase 
the convergence parameters, more likely the k-points and the cutoff.

kind regards


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Dr. Lorenzo Paulatto
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