Theoretical Investigation of HER Mechanism Using Density Functional and Ab Initio Calculations

The quantum calculation gives the insight of reaction mechanism in chemistry. In this work, we predict hydrogen evolution reaction (HER) mechanism in Ni(abt) 2 (abt = 2‐aminobenzenethiolate) catalyst. Using density functional theory (DFT) and coupled‐cluster singles, doubles and perturbative triples (CCSD(T)) methods, we demonstrate the potential energy surface (PES) for the HER reaction result with two intermediate states (IM) and transition states (TS). Our result shows that the hydrogen atoms are migrated to Ni atom one by one from each of two amino groups. It indicates that the HER reaction in Ni(abt) 2 occurs following the ligand‐assisted metal‐centered H 2 production. Finally, two hydrogen atoms are merged in Ni atom site which generates hydrogen molecule. This would be meaningful prediction to understand the role of metal catalyst in HER reaction pathway.