You can set ibrav=0 and choose the lattice vectors you want Paolo
On Tue, 2014-12-16 at 01:22 +0530, Kondaiah Samudrala wrote: > Dear all, > > > I am still confused with notation of Ibrav=7 in pwscf. The IBRV=7 > primitive cell vectors in pwscf are quite different from any other. > See below for two cases of primitive vectors IBRAV=7 > Case1 > For. e.g. In pwscf primitive vectors of IBRV=7 are > crystal axes: (cart. coord. in units of a) > a(1) = ( 0.500000 -0.500000 c/a) > a(2) = ( 0.500000 0.500000 c/a ) > a(3) = ( -0.500000 -0.500000 c/a ) > Case 2 > On the other hand, generally people used as (from published papers) > crystal axes: (cart. coord. in units of a) > > a(1) = ( -0.500000 0.500000 c/a) > a(2) = ( 0.500000 -0.500000 c/a ) > a(3) = ( 0.500000 0.500000 -c/a ) . > > > This variation leads to changes in reciprocal vectors and then IBZ > path. From Wikipedia > (http://www.sciencedirect.com/science/article/pii/S0927025610002697) > and http://www.cryst.ehu.es/ , I obtained the IBZ path for case 2. > But, what about the IBZ path of case 1 primitive cell vectors?? Is > both are same ??? But Xcrysden showing something else than regular > Gamma, Z, Sigma, P and N points . > > > I feel puzzled, would some one give some idea about this? any help will be > appreciated > with regards > S. Appalakondaiah > PhD Student > University of Hyderabad > > > > > > > > > _______________________________________________ > Pw_forum mailing list > [email protected] > http://pwscf.org/mailman/listinfo/pw_forum -- Paolo Giannozzi, Dept. Chemistry&Physics&Environment, Univ. Udine, via delle Scienze 208, 33100 Udine, Italy Phone +39-0432-558216, fax +39-0432-558222 _______________________________________________ Pw_forum mailing list [email protected] http://pwscf.org/mailman/listinfo/pw_forum
