On Sunday 08 January 2006 08:01, sun jason wrote: > I'm not sure about whether the born effective charge tensor > should be symmetric in crystals.
in general they aren't. Note that the two indices refer to different things: the first to electric field polarization, the second to atomic displacement. Paolo -- Paolo Giannozzi e-mail: giannozz at nest.sns.it Scuola Normale Superiore Phone: +39/050-509876, Fax:-563513 Piazza dei Cavalieri 7 I-56126 Pisa, Italy
