On Aug 20, 2009, at 17:11 , ali kazempour wrote: > I use vc-relax to optimize the lattice constant and also the > position for bulk. > After I make supercell with these optimized value and run a scf > with similar > value as bulk. But the force as I listed below for some atom is > relatively more > than other
I see quite small forces. If you do a supercell, do not forget that you will not get exactly the same values as for the original cell, unless the k- point grid of the unit cell refolds into the k-point grid of the supercell Paolo --- Paolo Giannozzi, Dept of Physics, University of Udine via delle Scienze 208, 33100 Udine, Italy Phone +39-0432-558216, fax +39-0432-558222
