[Pw_forum] Question about Example10

[Paolo Giannozzi]

On Jan 13, 2007, at 6:58 , lan haiping wrote:

>  I have  a question about berry phase calculation for born effetive  
> charge implemented in espresso. [...] I could obtain  born  
> effective tensor of Pb site
> about  3.9 -3.92 e whenever i increase ecutoffrho , conv_thr or use  
> denser
> kmesh. But the born effective tensor of O sites , i.e . the three  
> diagonal
> elements are not consistent with the result  of Zhong et al (PRL. 
> 72.3618).
> The values i obtained are  -1.98 , -5.85, -1.90e  respectively for  
> 3 different
> directions.

did you try linear response? If you get the same result, that's it
P.
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Paolo Giannozzi, Democritos and University of Udine, Italy