Electron spin resonance studies of some manganese(II) complexes with heterocyclic ligands

Abstract

Electronic and e.s.r. spectra have been measured for the compounds MnL₄X₂(L =γ-picoline, X = Cl, Br, I, NCS; L =β-picoline, X = Cl, Br; L = 3,5-lutidine, X = Cl, Br, I; L = 3-ethylpyridine, X = Br; L = 3-bromopyridine, X = I, NCS; and L = 3,5-dichloropyridine, X = I), and for some complexes MnL₂X₂ with the same neutral ligands. The e.s.r. spectra of most of the 4:1 complexes show absorption away from g_eff= 2, and are interpreted in terms of the zero-field splitting parameters D and λ. The compounds have essentially axial symmetry, with D in the range 0·035 to 0·87 cm^–1, and λ close to zero.