xyz-Files

Files like GEOMETRY.xyz, TRAEJC.xyz, or ION+CENTERS.xyz are in Xmol-style xyz format, a simple text format that is directly supported by many visualization programs. The first line has the number of atoms, followed by a ``title'' line, and one line per atom with element symbol and x-,y- and z-coordinates in Angstrom. Additional three columns with forces or velocities are optional. In IONS+CENTERS.xyz also the Wannier centers are includes and labeled as element ``X''.

In CPMD coordinates are usually not wrapped back into the principal supercell. The IONS+CENTERS.xyz http is an exception, since the Wannier centers are only computed inside the principal supercell, also all coordinates are wrapped back into that cell. Thus for easy visualization it is to specify a suitable a reference point in the &CPMD section of the input http via the WANNIER REFERENCE keyword.