Should you compare total energy per atom or total energy per unit volume? Of course, you have to use well-converged cutoff and k-point sampling. ---------------------------------------------------- Duy Le Postdoctoral Associate Department of Physics University of Central Florida. Website: http://www.physics.ucf.edu/~dle
On Wed, Jan 16, 2013 at 3:25 AM, Lorenzo Paulatto < lorenzo.paulatto at impmc.upmc.fr> wrote: > On 16 January 2013 02:33, Tram Bui <trambui at u.boisestate.edu> wrote: > >> Dear QE Users, >> I ran the calculation for a simple 1x1x1 unit cell SiC (zinc blend >> structure) . The calculated total energy for when ibrav=2 (two atoms per >> cell) is different from when ibrav=0 (8 atoms per cell). Would you give me >> some information on why the total energy changes? >> > > > Dear Tram, > maybe you did not use 2 sets of k-points that map perfectly from one > system to the other. > > bests > > -- > Dr. Lorenzo Paulatto > IdR @ IMPMC -- CNRS & Universit? Paris 6 > phone: +33 (0)1 44275 084 / skype: paulatz > www: http://www-int.impmc.upmc.fr/~paulatto/ > mail: 23-24/4?16 Bo?te courrier 115, 4 place Jussieu 75252 Paris C?dex 05 > > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://pwscf.org/mailman/listinfo/pw_forum > -------------- next part -------------- An HTML attachment was scrubbed... URL: http://pwscf.org/pipermail/pw_forum/attachments/20130116/f51ee135/attachment.html
