Chemistry in Laser-Induced Plasmas: Formation of M–CC–Cl (M = Ag or Cu) and their Characterization by Rotational Spectroscopy

The new linear molecule Ag–CC–Cl has been detected and fully characterized by means of rotational spectroscopy. It was synthesized by laser ablation of a silver rod in the presence of a gaseous sample containing a low concentration of CCl₄ in argon, cooled to a rotational temperature approaching ∼1–3 K through supersonic expansion, and analyzed by chirped-pulse, Fourier transform microwave spectroscopy. Six isotopologues were investigated, and for each the spectroscopic constants B₀, D_J and χ_aa(Cl) were determined. The B₀ values were interpreted to give the following bond lengths: r(Ag–C) = 2.015(14) Å and r(C–Cl) = 1.635(6) Å, with r(CC) = 1.2219 Å assumed from an ab initio calculation at the CCSD­(T)/aug-cc-pV5Z level of theory. The Cu analogue Cu–CC–Cl was similarly identified and characterized.