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)