An efficient density functional for accurate molecular chemisorption and physisorption on transition metal surfaces*

Understanding molecular adsorption on transition metal surfaces underpins many problems in heterogeneous catalysis. Accurately predicting the adsorption energies has been a challenging task as simultaneously capturing chemical and van der Waals (vdW) interaction in a single density functional is difficult. In this work, we propose a new density functional [Opt(MS+rVV10)] by combining a semi-local meta-generalized gradient approximation (MGGA) Made Simple (MS) [1] with revised Vydrov-van Voorihs (rVV10) vdW correction[2], with two key parameters in MGGA-MS and one in rVV10 simultaneously refitted to the atomization energies of covalently bonded small molecules and the Ar₂ binding curve. The resulting Opt(MS+rVV10) functional is validated for 39 molecular adsorptions on transition metal surfaces[3], showing improved and balanced descriptions for both physisorption and chemisorption in comparison with popular vdW-corrected density functionals.

[1] J Sun, R Haunschild, B Xiao, et. al., J. Chem. Phys. 138, 044113 (2013)
[2] R Sabatini, T Gorni, S de Gironcoli, Phys. Rev. B 87, 041108 (2013)
[3] J Wellenorff, T L. Silbaugh, D Gracia-Pintos, et. al., Surf. Sci. 640, 36-44 (2015)