ELECTRON SPIN RESONANCE SPECTRUM OF A NEW RADICAL PRODUCED BY REDUCTION OF TETRASULFUR TETRANITRIDE AND ITS IDENTIFICATION AS RADICAL ANION OF TETRASULFUR TETRANITRIDE

At temperatures below 0°, chemical or electrolytic reduction of S4N4 in tetrahydrofuran produces a nine-line esr spectrum characteristic of a radical with four equivalent nitrogens. The isotropic spin Hamiltonian parameters obtained from the observed spectrum, A(14N) = 1.185 G and g = 2.0006, are significantly different from those found by Chapman and Massey, who produced a nine-line spectrum by room-temperature reduction of S4N4 and assigned it to the radical anion S4N4−. Theoretical comparison of the g values and 14N hyperfine coupling constants of both nine-line radicals shows that only the low-temperature species has the characteristics expected for S4N4−. This interpretation is supported by the observed chemical behavior of the low-temperature radical, which decomposes at higher temperatures with a series of products which appear to be precursors of the radical found by Chapman and Massey. © 1969, American Chemical Society. All rights reserved.