Partially deorbitalized meta-GGA

Abstract

Mejia-Rodriguez and Trickey recently proposed a procedure for removing the explicit dependence of meta-GGA exchange-correlation energy functionals $E_{\mathrm{xc}}$ on the kinetic energy density $\tau$. We present a simple modification to this approach in which the exact Kohn-Sham $\tau$ is used as input for $E_{\mathrm{xc}}$ but the functional derivative of $\tau$ with respect to the density $\rho$, required to calculate the potential term $\int d^3{r}^{\prime }\delta E_{\mathrm{xc}}/\delta \tau ({\mathbf{r}}^{\prime }){|}_{\rho }\cdot \delta \tau ({\mathbf{r}}^{\prime })/\delta \rho (\mathbf{r})$, is evaluated using an approximate kinetic energy density functional. This ensures that the Kohn-Sham potential is a local multiplicative function as opposed to the non-local potential of a generalized Kohn-Sham approach. Electronic structure codes can be easily modified to use the new method. We validate it by quantifying the accuracy of the predicted lattice parameters, bulk moduli, magnetic moments and cohesive energies of a large set of periodic solids. An unanticipated benefit of this method is to gauge the quality of approximate kinetic energy functionals by checking if the self-consistent solution is indeed at the variational minimum.

References in corpus (17)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Climbing the Density Functional Ladder: Non-Empirical Meta-Generalized Gradient Approximation Designed for Molecules and Solids
• Optimization Algorithm for the Generation of ONCV Pseudopotentials
• SCAN+rVV10: A promising van der Waals density functional
• Rungs 1 to 4 of DFT Jacob's ladder: extensive test on the lattice constant, bulk modulus, and cohesive energy of solids
• More-Realistic Band Gaps from Meta-Generalized Gradient Approximations: Only in a Generalized Kohn-Sham Scheme
• Laplacian-level density functionals for the kinetic energy density and exchange-correlation energy
• Deorbitalized meta-GGA Exchange-Correlation Functionals in Solids
• Deorbitalization strategies for meta-GGA exchange-correlation functionals
• Meta-GGA Performance in Solids at Almost GGA Cost
• Density Functional Methods for the Magnetism of Transition Metals: SCAN in Relation to Other Functionals
• Shortcomings of meta-GGA functionals when describing magnetism
• Analysis of over-magnetization of elemental transition metal solids from the SCAN Density Functional
• Performance of the r${}^2$SCAN functional in transition metal oxides
• Non-collinear density functional theory
• Kinetic-Energy Density-Functional Theory on a Lattice
• Universal lower bounds on the kinetic energy of electronic systems with noncollinear magnetism