Observation of unsaturated platinum carbenes Pt2C2n− (n = 1–3) clusters: A photoelectron imaging spectroscopic and theoretical study

The structural and bonding properties of the Pt2C2n− (n = 1–3) complexes have been investigated by mass-selected photoelectron velocity-map imaging spectroscopy with quantum chemical calculations. The adiabatic detachment energies and vertical detachment energies of Pt2C2n− have been obtained from the measured photoelectron imaging spectra. Theoretical results indicate that the lowest-energy isomers of Pt2C2n− (n = 1–3) possess linear chain-shaped configurations. The binding motif in the most stable isomer of Pt2C2− has a linear cumulenic structure with a Pt=C=C=Pt configuration, and the structural characteristic persists up to all the lowest-energy isomers of the Pt2C4− and Pt2C6− anions. The chemical bonding analyses indicate that the Pt2C2n− (n = 1–3) complexes have multicenter two-electron characteristics.