Structures and bonding properties of CPt2 -/0 and CPt2H-/0: Anion photoelectron spectroscopy and quantum chemical calculations.

We present a combined anion photoelectron spectroscopic and quantum chemical investigation on the structures and bonding properties of CPt2 -/0 and CPt2H-/0. The experimental vertical detachment energies of CPt2 - and CPt2H- are measured to be 1.91 ± 0.08 and 3.54 ± 0.08 eV, respectively. CPt2 - is identified as a C2v symmetric Pt-C-Pt bent structure, and CPt2 has a D∞h symmetric Pt-C-Pt linear structure. Both anionic and neutral CPt2H adopt a Pt-C-Pt-H chain-shaped structure, in which the ∠PtCPt and ∠CPtH bond angles of CPt2H- are larger than those of CPt2H. The Pt-C bonds in CPt2 -/0 and CPt2H-/0 exhibit covalent double bonding characters. The Pt=C bonds are much stronger than the C-H bond that may explain why the C atom CPt2H-/0 prefers to form Pt=C bonds rather than C-H bonds. It may also explain why platinum can insert into the C-H bond to activate the C-H bond as reported in the literature.