On Jul 27, 2012, at 10:39 , Davide Tiana wrote: > As remembered in many QE tutorials, weights are meaningless in NSCF > calculations such as band ones.
yes and no, actually. 'nscf' calculation. The output data is meant to be used in subsequent calculations performing integrals over the BZ (e.g. dos); symmetry is applied and occupancies are calculated (using weights among other things) as for the 'scf' case 'band' calculation. Tthe output data is meant to be used only for visualization; symmetry is not applied, occupancies need not to be calculated, weights are in principle not used. Since the latest release, however, weights are used in the 'band' case as well to re-compute occupancies, because there is a specific case in which data to be exported to another code (not part of QE) have to be calculated using 'band' and not 'nscf', for reasons related to the way symmetries are handled. So, in conclusion: while weights in 'band' calculations are in most cases meaningless, it is a good idea not to fill them with absurd numbers (e.g. all zero or negative or very large) because the code could complain when calculating occupancies P. --- Paolo Giannozzi, Dept of Chemistry&Physics&Environment, Univ. Udine, via delle Scienze 208, 33100 Udine, Italy Phone +39-0432-558216, fax +39-0432-558222
