CASTEP is a software package originally created by Prof. M.D. Payne which uses density functional theory to provide a good atomic-level description of all manner of materials and molecules. CASTEP can give information about total energies, forces and stresses on an atomic system, as well as calculating optimum geometries, band structures, optical spectra, phonon spectra and much more. It can also perform molecular dynamics simulations. Whilst Materials Studio is only available on MS Windows running on PC-compatible hardware, CASTEP itself is officially supported on PCs with MS Windows or Linux, HP Alphas with Tru64, and SGIs with Irix, in both serial and MPI-parallel versions.

Citation: "CASTEP," CASTEP Development Group.

Launch Site

On-line tutorials in using CASTEP and concerning DFT in general are available.

Recommended reading:
S. J. Clark, M. D. Segall, C. J. Pickard, P. J. Hasnip, M. J. Probert, K. Refson, M. C. Payne, "First principles methods using CASTEP," Zeitschrift für Kristallographie, 220(5-6) pp.567-570 (2005).

Also see Materials Studio.