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Lithium benzoate containing 95 atom% lithium-6 (abbreviation: enriched) was tritiated by neutron irradiation in a pile. The degree of tritium incorporation to the benzene ring was 6.9 to 7.6 times that for the benzoate of natural isotopic abundance (abbreviation: natural abundance) according to the sample size, i.e., the geometries of irradiation samples were compared under the same thermal neutron fluence. The computed self-shielding effect for incident neutrons was negligible in the irradiation of the latter benzoate, while in the case of the former one rather large effects were observed in thick samples used in the present experiment. The tritium distribution in the benzene ring showed a slight ortho orientation in the irradiation of enriched ⁶Li compound, but was almost uniform in the other compounds. Copyright © 1998 John Wiley & Sons, Ltd.

Light induced tritiation of benzonitrile with diethylamine[N3H] or triethylamine-tritiated water was studied with respect to quenching of benzonitrile fluorescence by the amines and the tritium distribution in the nucleus. A mechanism involving an exciplex possessing charge transfer nature was proposed.

Bis(2-phenylbenzoyl) peroxide (2-PhBPO) was found to decompose on singlet and triplet sensitized irradiations in benzene and carbon tetrachloride. The quantum yields were determined to be 0.48 and 0.43 on direct excitation and chrysene sensitization in benzene, respectively, and 0.62 and 0.60 on benzophenone and 3′-methoxyacetophenone sensitizations in carbon tetrachloride, respectively. The reaction mechanisms are discussed from the standpoint of the modes of bond cleavage.

Methyl benzoate was tritiated at both nuclear and methyl positions on irradiation with diethylamine-N-tin benzene and with triethylamine–tritiated water in acetonitrile.

The temperature effect on the Na hyperfine splittings in electron spin resonance of the naphthalene-Na system in solution is investigated theoretically. Assuming that the motion of Na positive ion under the electro-static field of the naphthalene negative ion is harmonic along the long axis of the naphthalene molecule, the temperature dependence of the Na hyperfine splittings is interpreted through the weight factor of the Boltzmann distribution. At room temperature the Na positive ion is found with largest probability to locate nearly above the center of one of the benzene rings in naphthalene, and at this position one obtains a reasonable order of magnitude for the Na hyperfine coupling constant.