Toward an All-Around Semilocal Potential for Electronic Exchange

Abstract

We test local and semi-local density functionals for the electronic exchange for a variety of systems including atoms, molecules, and atomic chains. In particular, we focus on a recent universal extension of the Becke-Johnson exchange potential [Räsänen, E.; Pittalis, S.; Proetto, C. R. J. Chem. Phys. 2010, 132, 044112]. It is shown that when this potential is used together with the Becke-Roussel approximation to the Slater potential [Becke, A. D.; Roussel, M. R. Phys. Rev. A 1989, 39, 3761-3767], a good overall agreement is obtained with experimental and numerically exact results for several systems, and with a moderate computational cost. Thus, this approximation is a very promising candidate in the quest for a simple and all-round semi-local potential. * Electronic address: micael@teor.fis.uc.pt; Present address

Calculating energy loss spectra of NiO: Advantages of the modified Becke-Johnson potential

“…15 Kim et al 16 applied the TB-mBJ potential on III-V semiconductors, while Pittalis et al 17 extended the Becke-Johnson potential for use on two-dimensional systems. Räsänen et al 18 provided a different correction of the Becke-Johnson potential, which Oliveira et al 19 compared to experiments for atoms, molecules, and atomic chains.…”

A generalized gradient approximation for exchange derived from the model potential of van Leeuwen and Baerends

“…2 Examples of model Kohn-Sham potentials include the Krieger-Li-Iafrate approximation, 3 the gradientcorrected exchange-correlation potential of van Leeuwen and Baerends, 4 and the Becke-Johnson exchange potential 5 with its extensions. [6][7][8][9][10] Several reports in the recent literature 6,[11][12][13][14] suggest that direct approximation of Kohn-Sham potentials is a promising route to accurate prediction of static electric polarizabilities, band gaps, and other properties.…”

Orbital Localization, Charge Transfer, and Band Gaps in Semilocal Density-Functional Theory

“…A recent model potential of Becke and Johnson (BJ) [14] has with various modifications shown improved polarizabilities [15], band gaps [16,17], and atomic and molecular properties [18,19]. It was discovered that one of its decisive positive aspects is that its asymptotic limiting value outside a finite system depends on the eigenvalue of the highest occupied orbital (HOMO), but not its occupation number [14,15].…”