The Fourier transform microwave spectrum of YC2 () and its 13C isotopologues: Chemical insight into metal dicarbides

The Fourier transform microwave spectrum of YC2 ( X ˜ 2 A 1 ) and its 13C isotopologues has been measured in the 10–57 GHz range, the first FTMW study of a metal dicarbide species. The molecule was created from yttrium vapor and CH4 in argon in a supersonic jet with a discharge-assisted laser ablation source (DALAS). Rotational, fine structure, and Y and 13C hyperfine constants were determined for each isotopologue. The calculated r m ( 1 ) structure is r(Y–C) = 2.187(4) Å, r(C–C) = 1.270(4) Å, and θ(C–Y–C) = 33.74(7)°. The hyperfine parameters indicate that the unpaired electron resides principally in an sd hybridized orbital on the yttrium nucleus.