The electron-spin resonance spectrum of a phosphorane radical cation trapped in a crystalline matrix

Abstract

X-Irradiation of single crystals of carboxymethyltriphenylphosphonium chloride produces the corresponding oriented phosphorane radical-cation Ph₃[graphic omitted]ĊH·CO₂H. The spectrum has been analysed to yield the hyperfine coupling tensors of the ¹H and ³¹P nuclei and the g-tensor. These values are discussed in terms of the possibility of delocalisation of the unpaired electron in a 3d orbital of the phosphorus atom.