Correlation functional in screened-exchange density functional theory procedures

5 years ago

Correlation functional in screened-exchange density functional theory procedures

Kimihiko Hirao, Yukio Kawashima, Bun Chan

In the present study, we have explored several prospects for the further development of screened-exchange density functional theory (SX-DFT) procedures. Using the performance of HSE06 as our measure, we find that the use of alternative correlation functionals (as oppose to PBEc in HSE06) also yields adequate results for a diverse set of thermochemical properties. We have further examined the performance of new SX-DFT procedures (termed HSEB-type methods) that comprise the HSEx exchange and a (near-optimal) reparametrized B97c (cOS,0 = cSS,0 = 1, cOS,1 = −1.5, cOS,2 = −0.644, cSS,1 = −0.5, and cSS,2 = 1.10) correlation functionals. The different variants of HSEB all perform comparably to or slightly better than the original HSE-type procedures. These results, together with our fundamental analysis of correlation functionals, point toward various directions for advancing SX-DFT methods. © 2017 Wiley Periodicals, Inc. We have re-formulated the HSE procedure using a B97-type correlation functional to enable further development of screened-exchange (SX) DFT. The new “HSEB-type” procedures have the following re-determined B97c parameters: cOS,0 = cSS,0 = 1, cOS,1 = −1.5, cOS,2 = −0.644, cSS,1 = −0.5, and cSS,2 = 1.10. We have demonstrated that, even with just near-optimal parametrization, HSEB already performs comparably to or slightly better than HSE for thermochemistry, molecular structure, and semiconductor bandgap.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/jcc.24882