PHON_G_CUTOFF

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Revision as of 09:40, 20 July 2022 by Tal (talk | contribs)

PHON_G_CUTOFF = [3x3xNIONS real] 

Default: PHON_G_CUTOFF = None

Description: PHON_G_CUTOFF sets the cutoff radius in reciprocal space used to determine the number of vectors involved in the Ewald sum in polar phonon calculations.


If the material is polar (i.e. has more than one atom type), a special treatment of the long-range dipole-dipole interaction is required to obtain a smooth phonon dispersion. This is activated by setting LPHON_POLAR=.TRUE. and supplying the static dielectric tensor (PHON_DIELECTRIC) and the Born-effective charges (PHON_BORN_CHARGES) which can be obtained in a separate VASP calculation using the LEPSILON or LCALCEPS tag. The long-range part is evaluated using an Ewald sum with the number of vectors in reciprocal space being determined using a cutoff length (PHON_G_CUTOFF).

Mind: Only available as of VASP 6.3.2.

Related tags and articles

QPOINTS, LPHON_DISPERSION, PHON_NWRITE, LPHON_POLAR, PHON_DIELECTRIC, PHON_BORN_CHARGES

Examples that use this tag