Overview

One of the most fundamental tasks for CASTEP is to take a crystal lattice and set of atomic positions, and compute the electronic density and total energy.

Once the lattice and atomic positions have been specified, you can tell CASTEP to compute the energy by setting the task keyword in the param file:

task : energy

Your cell and param files should be named using the same prefix, which CASTEP calls the "seedname", and the extensions .cell and .param, respectively. For example, for a calculation called mytest, you need the input files

mytest.cell
mytest.param

and the calculation is run with the command

castep mytest

CASTEP computes the energy by solving the Kohn-Sham equations iteratively, using the 'self-consistent field' (SCF) method.