After x supercell you must "modify" the resulting struct file. Possible modifications depend on the purpose of your supercell calculations, eg. replace/remove an atom (or "mark" one with labelling an atom as eg. "Ti1", eventually after "splitting" equivalent positions); or displace some atoms, .....
You cannot do a supercell calculation without modifications, i.e. reducing the symmetry. I bet, sgroup would have reduced your structure back to the original one. Dear Wien2k users! I have generated a 2x2x2 supercell from a hexagonal lattice. Upon initializing the calculation and after "copy struct_st" I get a warning "You must move the origin (see file *.outputs)" In the outputs file (given below) I fing that "PGBSYM: SPACE GROUP CONTAINS INVERSION BUT ATOMS SHOULD BE SHIFTED BY 2.51292470 1.45083775 12.96923800" There are also some errors to be found further down the file. E.g. : "---------- ERROR ------------------ The (multiplicity of this atom)*(number of pointgroup-operations) is NOT = (number of spacegroup-operations) MULT: 16 ISYM: 12 NSYM 24 Check your struct file with sgroup -wien case.struct -- ----------------------------------------- Peter Blaha Inst. Materials Chemistry, TU Vienna Getreidemarkt 9, A-1060 Vienna, Austria Tel: +43-1-5880115671 Fax: +43-1-5880115698 email: pblaha at theochem.tuwien.ac.at -----------------------------------------