Dioxygen Binding to all 3d, 4d, and 5d Transition Metals from Coupled-Cluster Theory.

Abstract

Understanding how transition metals bind and activate dioxygen (O2 ) is limited by experimental and theoretical uncertainties, making accurate quantum mechanical descriptors of interest. Here we report coupled-cluster CCSD(T) energies with large basis sets and vibrational and relativistic corrections for 160 3d, 4d, and 5d metal-O2 systems. We define four reaction energies (120 in total for the 30 metals) that quantify O-O activation and reveal linear relationships between metal-oxygen and O-O binding energies. The CCSD(T) data can be combined with thermochemical cycles to estimate chemisorption and physisorption energies for each metal from metal oxide embedding energies, in good correlation with atomization enthalpies (R2 =0.75). Spin-geometry variations can break the linearities, of interest to circumventing the Sabatier principle. Pt, Pd, Co, and Fe form a distinct group with the weakest O2 binding. R2 up to 0.84 between surface adsorption energies and our energies for MO2 systems indicate relevance also to real catalytic systems.