A single geometric isomer of benzoyliminoxyl radical (1) is formed upon inclusion of 1-phenylpropa-1,2-dione-2-oxime (2) in the pores of a pentasil zeolite (ZSM-5). The EPR powder pattern observed in this matrix shows unambiguously that the principal axes of the 14N and 1H dipolar hyperfine couplings, AN,∥ and AH,∥, respectively, are nearly perpendicular to each other. A comparison of the directions expected for the two geometric isomers identifies the spin Hamiltonian parameters as those of the Z isomer. The direct evidence contained in the dipolar hyperfine interactions (A∥) is supported by indirect evidence derived from long-range isotropic hyperfine interactions (Aiso).
All Science Journal Classification (ASJC) codes
- Physical and Theoretical Chemistry