Dear Stefano: I'm using Ultrasoft PPs. My question was because this cutoff (20 Ry) seemed to be appropriate for other carbonic systems.
[]s, Roberto Stefano Baroni <baroni at sissa.it> wrote: On May 9, 2008, at 10:42 PM, Roberto G. A. Veiga wrote: Hi, Konstantin: thank you very much. Such a large cutoff (80 Ry) is necessary for convergence? Or maybe I'm using one quite small (20 Ry)... it depends on the PP you are using, I guess, and certainly NOT on the actual structure you are studying. 80 Ry seems like an appropriate cutoff for moderately hard norm-conserving PP's, whereas 20 Ry sounds like appriate for many US PP's. In either case, you better check the aprporiateness by yourself, through thorough convergence tests. Stefano []s, Roberto Konstantin Kudin <konstantin_kudin at yahoo.com> wrote: Hi Roberto, Here is a ribbon input that works for sure: https://kiev.princeton.edu/misc/rg_07.scf.in (get PPs from the PWSCF website) Good luck! Kostya --- Stefano Baroni - SISSA & DEMOCRITOS National Simulation Center - Trieste [+39] 040 3787 406 (tel) -528 (fax) / stefanobaroni (skype) La morale est une logique de l'action comme la logique est une morale de la pens?e - Jean Piaget Please, if possible, don't send me MS Word or PowerPoint attachments Why? See: http://www.gnu.org/philosophy/no-word-attachments.html _______________________________________________ Pw_forum mailing list Pw_forum at pwscf.org http://www.democritos.it/mailman/listinfo/pw_forum --------------------------------- Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20080510/1991e752/attachment-0001.htm
