NUCLEAR CHEMISTRY RESEARCH. Annual Progress Report

Abstract

The results of experiments and planned work of the Department of Chemistry, Arkansas University, in nuclear chemistry and physics, theoretical physics, and organic isotope chemistry are discussed. The absolute activation cross sections for 14.8-Mev neutrons were determined for a large number of isotopes, and a new isotope was found in the Fe/sup 54/(n,t) reaction. The (n,2p) reaction was studied in detail. A number of (n,He/sup 3/) and (n,t) reactions were studied. A literature survey (up to 1958) was made for cross sections of neutron-induced reactions around 14 Mev. The (n,p) reaction survey was continued up to date. The literature data have a large spread with factors of 2 to 10. Equations were derived from the (n,p) data giving the cross section as a function of atomic number and mass. The yields for U/sup 238/ 14-Mev fission were measured at mass numbers were studied. The theoretical aspects of molecular excitation resulting from beta decay of a constituent atom are being studied. Calculations were made on the wave functions of the ground state of the helium atom. The acid-catalyzed rearrangements of ketones were studied with both labeled and unlabeled compounds. No cyclic ketones were found to rearrange. The mechanism of the oxygen exchange between benzyl and substituted benzyl alcohols and water was studied with O/sup 18/ tracer. The oxygen exchange between water and benzophenones was also studied. The chlorine isotope effects in displacement reactions of benzyl and substituted benzyl chlorides with various nucleophiles were investigated; the results show a relation between isotope effect and reaction kinetic order. The C/sup 14/ isotope effect on the S/sub N/2' reaction of 3-chloro-1-butene-1-C /sup 14/ with diethylamine was measured. A preliminary measurement was made of the N/sup 15/ isotope effect in the Curtis rearrangement. (See also ORO-182.) (D.L.C.)