Range-separated hybrids combining a range-separated Perdew-Burke-Ernzerhof functional with exact exchange and random phase approximation correlation
Irelan, Robert M
Scuseria, Gustavo E.
Master of Science
Previous methods of combining a short-range density functional approximation with treatment of the long range using exact exchange and random phase approxi- mation correlation have been extended by replacing a range-separated local density approximation in the short range with a range-separated generalized gradient ap- proximation functional that is generally much more accurate for molecular systems. The coefficients for range separation and for the fraction of random phase approxi- mation correlation are optimized based on thermodynamic test set data. The new functional is shown to retain or markedly improve the accuracy of calculations on test set data compared to previous attempts to combine short-range density functional approximations with long-range exact exchange and random phase approximation correlation while retaining its performance in describing long-range van der Waals interactions.