Electronic structure and hyperfine interactions for hydrazyl radicals

Some aspects of electronic structure and hyperfine interactions for α,α-diphenyl-β-picrylhydrazyl and its derivatives have been studied. High resolution EPR spectra have been obtained and analyzed by the least-quares method in Fourier space. The results obtained are confirmed by NMR experiments. Anisotropic EPR spectra of hydrazyl radicals in frozen solutions and glasses have been recorded. Parameters of hyperfine tensors and g-tensor have been determined by the least-squares method. Spin distributions in radical molecules are calculated by the unrestricted Hartree—Fock method and calculations of isotropic and anisotropic hyperfine interactions have been carried out.