Superhyperfine structure of the ESR spectrum of the Cu⁺² ion in the ZnWO₄ lattice

Abstract

When present in the ZnWO₄ lattice in quantities of less than 0.005%, the Cu⁺² ion exhibits an ESR spectrum with a superhyperfine structure of the ligand type at liquid-helium temperature. This is due to the interaction of the 3d⁹ electrons of the Cu⁺² ion with the nuclear magnetic moments of the W¹⁸³ isotopes (14.4%) lying along the z axis; the superhyperfine interaction constant is equal to 7.4±0.4 G. On increasing the concentration of the Cu⁺² ions the superhyperfine structure of the spectrum no longer appears. Calculations of the intensities of the spectral components agree satisfactorily with experimental data.