in neat (no solvent, gas phase) Electric Arc; Ar; a gas mixt. at 40 psi pressure injected with a pulsed mol. beam valve (General Valve, series 9) into a flow channel prior to supersonic expansion into a vac. chamber, struck a discharge between a pair of stainless steel ring electrodes;

evapn. at 900°C; gas mixt. is passed through a cell which is heated to 1750°C; isolated in solid Ne-matrix at 4 K;