in gaseous matrix byproducts: cyclic C6; heating in oven cycling between 2000 and 3000 K, co-condensation of vapors with Ar onto CsI substrate (10 K);

in gaseous matrix Irradiation (UV/VIS); (12)C/(13)C rod in various isotopic ratios vaporizationby 532 nm Nd:YAG pulsed laser, vaporized species codeposition with Ar on Au plated surface cooled to ca. 10 K in vac. 1E-7 Torr or better;