Electron Parameagnetic Resonance of the CH2CO2(-) Radical in Irradiated Zinc Acetate Dihydrate.

• Main Author: Crawford, Leslie Paul
• Other Authors: Naval Postgraduate School (U.S.)
• Language: en_US
• Published: Monterey, California. Naval Postgraduate School 2014
• Online Access: http://hdl.handle.net/10945/40058

Approved for public release, distribution unlimited === No PDF currently available. === An electron paramagnetic resonance study of the CH2CO2(-) radical in irradiated zinc acetate dihydrate has been made. The configuration of the radical in the crystalline lattice has been determined as nearly planar using a least squares fit. The HCH angle was found and the principal elements of the alpha-proton hyperfine tensors were calculated. Three principal values of the g tensor were selected for the best least squares fit: 2.00242, 2.00353, 2.0043. By experiment and an MO calculation the radical has been shown to be a pi-electron radical with the unpaired electron localized on the alpha-carbon. Satellite lines were observed and interpreted as possible 'spin-flip' transitions. A temperature dependence of the coupling constants for the 2 protons was discovered from spectra taken at room temperature and at 133K. Single crystals of Zn(CH2DCO2)2.2H2O were irradiated and an analysis of the spectra showed that the barrier to formation of the radical was the breaking of the C-H bond on the undamaged acetate ion.