Thanks a lot for explaining, Lorenzo. Perhaps using "right" and "wrong" is not suitable to describe problem. They just meant the symmetry which I intend to get or not. Follow your instructions, I get the "right" symmetry which I intend to. I think I know "how" to solve this problem now. And I have to spend more time to learn about FFT grid so as to totally understand "why" doing this way.
L & P, Thank you again! ----- Original Message ----- From: "Paolo Giannozzi" <[email protected]> To: "PWSCF Forum" <pw_forum at pwscf.org> Sent: Wednesday, April 22, 2009 6:34 PM Subject: Re: [Pw_forum] improper symmetry analysis > Lorenzo Paulatto wrote: > >> If I remember correctly symmetry is applied only on the FFT grid, the >> dimensions of the smooth grid should not matter. > > you remeber correctly, but actuyally there is no ]strong reason for > such choice: the part of the charge density that has to be symmetrized > is calculated in the smooth grid > >> Likely they are too small with respect to what your cutoffs requires! > > one can try to reduce a little bit the fft dimensions, but success is > not guaranteed! anyway the code should loudly complain > > P. > -- > Paolo Giannozzi, Democritos and University of Udine, Italy > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum
