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CASTEP is software for calculating the properties of materials. It models various properties including energetics, atomic structure, vibrational properties, electronic response etc.

CASTEP is available as a module on Apocrita. Both serial (castep.serial) and MPI versions (castep.mpi) are available.


CASTEP requires avx2 instructions and therefore must be run on SDV or NXV nodes. This can be achieved using the -l avx2 option in your job script. For InfiniBand jobs the -l infiniband= setting will select the appropriate nodes for you (either sdv-i or sdv-ii).

To run the default version of CASTEP, simply load the castep module:

$ module load castep
$ castep.serial
castep <seedname>                : Run files <seedname>.cell [and <seedname>.param]
  "    [-d|--dryrun] <seedname>  : Perform a dryrun calculation on files <seedname>.cell
  "    [-s|--search] <text>      : print list of keywords with <text> match in description
  "    [-v|--version]            : print version information
  "    [-h|--help] <keyword>     : describe specific keyword in <>.cell or <>.param
  "         "      all           : print list of all keywords
  "         "      basic         : print list of basic-level keywords
  "         "      inter         : print list of intermediate-level keywords
  "         "      expert        : print list of expert-level keywords
  "         "      dummy         : print list of dummy keywords

For full usage documentation, run castep.serial -h.


To use castep you must contact us and provide evidence that you have a licence to use the software.

Example jobs

Note the use of ${NSLOTS} in the parallel example to ensure that cores are used properly.

Serial job

Here is an example job running on 4 cores and 8GB of memory:

#$ -cwd
#$ -j y
#$ -pe smp 4
#$ -l h_rt=1:0:0
#$ -l h_vmem=2G
#$ -l avx2

module load castep/18.1-intel

castep.serial diamond

Parallel job

Here is an example job running on 48 cores across 2 sdv nodes with MPI:

#$ -cwd
#$ -j y
#$ -pe parallel 48
#$ -l infiniband=sdv-i
#$ -l h_rt=240:0:0

module load castep/18.1-intel

mpirun -np ${NSLOTS} castep.mpi hex