Electron spin resonance and structure of the ionic radical, ·PO3=

Abstract
It is shown that the ionic radical, ·PO3 =, is formed by the action of γ-rays on disodium ortho-phosphite pentahydrate. The hyperfine coupling to the 31P nucleus has principal values of 1967, 1514 and 1513 Mc/s and is consistent with a pyramidal ion having OPO angles of 110°.