CASTEP file formats - PARAM

The .param file contains all of the control parameters required to run a CASTEP job, including the type of calculation, the charge, the spin state, and convergence tolerances. The file consists of lines containing keywords and associated values.

A .param file is generated by Materials Studio when you launch a calculation or when you click the Save Files button on the CASTEP Job Files dialog. Job options selected using the interface appear as keywords in the resulting .param file.

Under certain circumstances, you may wish to manually add keywords to a .param file. The procedure is described in the topic Running CASTEP in standalone mode.

The following rules govern keywords in the .param file:

Keywords may appear in any order.
The keywords and values are case- and punctuation-insensitive.
Only one keyword and its options may appear on a line.
Keywords that do not appear in the .param file are set to their default values.
Units may be specified for physical quantities.

Recognized units and their identifiers are listed in the UNIT keyword topics. If no units are specified, the default units will be assumed.

Comment lines (those beginning with #, ;, ! or COMMENT) and blank lines are ignored.

Keywords and their values are fully described in the topic CASTEP keywords.

CASTEP file formats - PARAM

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