Range-separated DFT functionals
Posted: Tue Jul 08, 2014 12:15 am
Does anyone know if it is possible to use a RSH such as LC-wPBE or LC-wPBE0 in VASP?
From reading the source code, it would appear that setting LRHFCALC=.TRUE. will allow for semi-local short range exchange and long-range HF exchange. But setting this tag also sets a default value of AEXX=1.0; this would seem to correspond to a default full-HF calculation, unless somehow in conjunction with LRHFCALC=.TRUE., AEXX now controls the fraction of short-range semi-local exchange. Presumably, AEXX can also be set in the INCAR but I am confused by the default value to begin with.
From reading the source code, it would appear that setting LRHFCALC=.TRUE. will allow for semi-local short range exchange and long-range HF exchange. But setting this tag also sets a default value of AEXX=1.0; this would seem to correspond to a default full-HF calculation, unless somehow in conjunction with LRHFCALC=.TRUE., AEXX now controls the fraction of short-range semi-local exchange. Presumably, AEXX can also be set in the INCAR but I am confused by the default value to begin with.