Van der Waals density functional: An appropriate exchange functional

Article

关键词: GENERALIZED GRADIENT APPROXIMATION;    NONCOVALENT INTERACTIONS;    STACKING INTERACTIONS;    INTERACTION ENERGIES;    ACCURATE;    DNA;    MODEL;   

DOI  :  10.1103/PhysRevB.81.161104

来源: SCIE

【 摘 要 】

In this Rapid Communication, an exchange functional which is compatible with the nonlocal Rutgers-Chalmers correlation functional [van der Waals density functional (vdW-DF)] is presented. This functional, when employed with vdW-DF, demonstrates remarkable improvements on intermolecular separation distances while further improving the accuracy of vdW-DF interaction energies. The key to the success of this three-parameter functional is its reduction in short-range exchange repulsion through matching to the gradient expansion approximation in the slowly varying/high-density limit while recovering the large reduced gradient, s, limit set in the revised Perdew-Burke-Ernzerhof (revPBE) exchange functional. This augmented exchange functional could be a solution to long-standing issues of vdW-DF lending to further applicability of density-functional theory to the study of relatively large, dispersion bound (van der Waals) complexes.

【 授权许可】

Free