Angle Dependence of Paramagnetic-Resonance Line Intensities of TrivalentCr53in MgO

Abstract

Three methods have been used to predict paramagnetic-resonance line intensities in the spectrum of trivalent ${\mathrm{Cr}}^{53}$ in sites of tetragonal symmetry in MgO. The methods are: numerical diagonalization of the Hamiltonian matrix, perturbation theory, and a technique involving the magnetic field induced at the nucleus by the electron spin. Experimentally observed line intensities are compared with the calculated intensities. The induced-field method is found to adequately describe the spectrum and to agree very closely with results from numerical diagonalization of the Hamiltonian. Some small discrepancies in line positions are observed which imply an inaccuracy in the usual axial-field spin Hamiltonian.