The electron spin resonance powder spectrum of ReIV in TiO2

Abstract

The X- and Q-band e.s.r. powder spectra of TiO₂: Re are calculated with a computer program that allows the use of any spin-Hamiltonian with terms bilinear in spin and field operators. The system is quite complicated: the electron spin S= 3/2 and Re has two isotopes each with I= 5/2. The anisotropy of the interaction tensors is very large: resonances are observed in sweep ranges of ca. 4500 G at X-band and ca. 10 500 G at Q-band. Features in the experimental X-band spectrum which could not be understood previously can be assigned after comparison with this simulated spectrum.