Accession Number : AD0716589

Title :   Chemical Reactions Induced by Ultraviolet and Ionizing Radiation.

Descriptive Note : Final rept. 1 Nov 69-31 Oct 70,

Corporate Author : CALIFORNIA INST OF TECH PASADENA DIV OF CHEMISTRY AND CHEMICAL ENGINEERING

Personal Author(s) : Hammond,George S.

Report Date : NOV 1970

Pagination or Media Count : 16

Abstract : Briefly discussed is research done in four areas: (1) special acceleration of nonradiative decay of excited states by specific quenchers, (2) photochemistry of bichromophoric compounds, (3) magnetic resonance studies, and (4) high energy radiation chemistry. The results in 1 and 2 have led to discovery of some interesting new photochemistry and to very tentative models as to the nature of the interactions in weakly coupled systems. Magnetic resonance work has been centered on two subjects. The rates of decay of various free radicals produced photochemically were observed. The kinetics depend on the solvent medium and indicate that solvent relaxation processes may make important contributions to variations in the rates of fast reactions in fluid media. Also studied were radicals by observing chemically induced polarization of nuclear spins (CIDNP) in reaction products. A careful study was done on the radiation induced dimerization of 1,3-cyclohexadiene, and it is believed that separation of excited state and ionic paths has been accomplished. (Author)

Descriptors :   (*PHOTOCHEMICAL REACTIONS, *QUENCHING(INHIBITION)), (*FREE RADICALS, PHOTOCHEMICAL REACTIONS), SCIENTIFIC RESEARCH, RADIATION CHEMISTRY, EXCITATION

Subject Categories : Radiation and Nuclear Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE