Recent laboratory photochemical studies and their relationship to the photochemical formation of cometary radicals

Experimental laboratory techniques used in studying the photochemistry of stable and unstable molecules are discussed. The laboratory evidence for the photochemical formation of C2 from C2H, C3 from C3H2, and NH from NH2 is presented. Other recent results obtained in laboratory studies of H2O, H2S, NH3, and HCN are reported.