This data block contains the external pressure tensor. Positive external pressure corresponds to compression and a negative pressure to tension. The data block has the following format:
%BLOCK EXTERNAL_PRESSURE [units] Rxx Rxy Rxz Ryy Ryz Rzz %ENDBLOCK EXTERNAL_PRESSURE
Where, Rxx is the xx-component of the pressure, Rxy is the xy-component, etc.
[units] specifies the units in which the pressure is defined. If no units are given, the default of Gigapascals is used.
By default, no external pressure is applied.
%BLOCK EXTERNAL_PRESSURE GPa 5.0000000000 0.0000000000 0.0000000000 5.0000000000 0.0000000000 5.0000000000 %ENDBLOCK EXTERNAL_PRESSURE
CASTEP keyword glossary
CASTEP cell keywords and data blocks