Accurate and Numerically Efficient r2SCAN Meta-Generalized Gradient Approximation

The recently proposed rSCAN functional J. Chem. Phys. 2019 150, 161101 is a regularized form of the SCAN functional Phys. Rev. Lett. 2015 115, 036402 that improves SCAN's numerical performance at the expense of breaking constraints known from the exact exchange-correlation functional. We construct a new meta-generalized gradient approximation by restoring exact constraint adherence to rSCAN. The resulting functional maintains rSCAN's numerical performance while restoring the transferable accuracy of SCAN.