Highly Unsaturated Platinum and Palladium Carbenes PtC(3) and PdC(3) Isolated and Characterized in the Gas Phase

Carbenes of platinum and palladium, PtC(3) and PdC(3), were generated in the gas phase through laser vaporization of a metal target in the presence of a low concentration of a hydrocarbon precursor undergoing supersonic expansion. Rotational spectroscopy and ab initio calculations confirm that both molecules are linear. The geometry of PtC(3) was accurately determined by fitting to the experimental moments of inertia of twenty‐six isotopologues. The results are consistent with the proposal of an autogenic isolobal relationship between O, Au(+), and Pt atoms.