PHON G CUTOFF: Difference between revisions

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Revision as of 08:23, 20 July 2022

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 G-vectors involved in the Ewald sum in polar phonon calculations.


If the material is polar (i.e. has more than one different 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 on a separate VASP run using the LEPSILON or LCALCEPS tag. The long-range part is evaluated using an Ewald sum with the number of G-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, PHON_DOS, PHON_SIGMA, PHON_NEDOS

Examples that use this tag