A single-crystal electron spin resonance study of manganese(II)-doped zinc maleate tetrahydrate

Abstract

The electron spin resonance spectra of single crystals of manganese(II)-doped zinc maleate tetrahydrate have been investigated at room temperature. The transitions arise from a single type of site with g_xx= 2.010, g_yy= 1.992, and g_zz= 2.035. The g shifts from the free spin value have been attributed to an electron-transfer process from the ligands to the S state ion. The observed angular variation of the allowed hyperfine transitions is in good agreement with theory. The spin-Hamiltonian parameters D= 360.5 × 10^–4, E= 66.8 × 10^–4, a=–8.9 × 10^–4, and A=–87.0 × 10^–4 cm^–1 have been deduced. From the A value an ionicity of 96.5% is derived for the metal–ligand bonding. The analysis of forbidden hyperfine transitions leads to Q′= 1.58 × 10^–4 and Q″= 0.28 × 10^–4 cm^–1 for the axial and rhombic components of the quadrupole coupling tensor respectively for the ⁵⁵Mn nucleus.