OPTICS_NEXTRA_BANDS (.param)

Keyword type

Integer

Description

This keyword controls the number of extra bands at each k-point in addition to the number of occupied bands, when performing an optical spectrum calculation.

It is not possible to have both the OPTICS_NBANDS keyword and either the OPTICS_NEXTRA_BANDS or OPTICS_PERC_EXTRA_BANDS keywords present in the same input file.

Default

0

The default value corresponds to a calculation of the optical spectrum for the valence band only. To calculate optical spectra for the conduction band use positive values of OPTICS_NEXTRA_BANDS.

Example

OPTICS_NEXTRA_BANDS : 36

See Also:

OPTICS_NBANDS
OPTICS_PERC_EXTRA_BANDS
CASTEP keyword glossary
CASTEP parameters keywords