This contains all of the parameters which the user requires within the calculation. The parameters can be specified in any
order but only one parameter must be specified per line. The most fundamental parameter is the task (there are other types
of CASTEP calculation besides geometry optimisation). A geometry optimisation .param file should always include the line
task : GeometryOptimization
Note the format
keyword : value
Most of the parameters (there are very many of them) can be left as defaults. The main parameters that the user may find
useful to specify and why are outlined below