On Nov 24, 2012, at 8:05 , Ker Park wrote: > fft-check warning: sum of imaginary terms = .1440955E-09 it's small, no problem here 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