DCD Files

The http TRAJEC.dcd contains the coordinates of the system in X-Plor, CHARMM style binary format. This is especially convenient for large systems (QM/MM) or long trajectories, since binary https load much faster and the http needs much less storage. Unlike the other trajectory formats supported by CPMD, DCD format https also contain supercell size and shape information, so periodic display is easier. On the other hand, DCD https contain no information about elements, so in programs like VMD, one first has to load, e.g., the GEOMETRY.xyz http and then load the coordinates from the DCD http on top of that. It may also be advantageous to first generate a PSF format http to define elements and bonding information.