Theoretical study of the protonation of [Pt3(μ-L)3(L′)3] (L = CO, SO2, CNH; L′ = PH3, CNH)

Ab initio calculations suggest that a series of clusters of the [Pt3(μ-L)3(L′)3(μ3-H]+ type (L = CO, SO2, CNH; L′ = PH3, CNH) are stable. We have studied these clusters at the HF, MP2, B3LYP, PBE and TPSS theory levels. The magnitude of the interaction energies and distances indicates a substantial covalent character of the Pt3–H bond, confirmed by orbital diagrams. In addition, the Fukui index of electrophilic attack and electrophilicity index on the unprotonated clusters were used to explore possible sites where chemical reactivity may play a role.