E. P. R.‐Studies of V2O5 Single Crystals. I. Defect Centres in Pure, Non‐stoichiometric Vanadium Pentoxide

Abstract

AbstractThe E.P.R.‐spectra of zone‐refined V2O5 are interpreted in terms of a defect centre consisting of an unpaired electron interacting with two equivalent vanadium nuclei separated by an oxygen vacancy. This conception leads to the establishment of a defect formula for V2O5, involving V4+ and V3+ ions. A self‐consistent mechanism is proposed for the formation of the low‐temperature form of non‐stoichiometry in V2O5. Principal values of the approximately axially‐symmetric spin‐Hamiltonian are