SINGLE-CRYSTAL EPR STUDY OF MN2-DOT 4H(2)O)( IONS IN COBALT MALEATE TETRAHYDRATE (CO(C4H3O4)(2) CENTER)

Electron paramagnetic resonance (EPR) studies have been carried out on Mn2+-doped cobalt maleate tetrahydrate single crystals in the tempera ture range 123-393 K on X-band frequency. The EPR spectrum at room tem perature exhibits a group of five fine structure transitions each spli t into six hyperfine components. It is found that Mn2+ enters the latt ice substitutionally and only one type of Mn2+ site is identified. The spin-Hamiltonian parameters were evaluated and discussed. The variati on of zero-field splitting parameter (D) as a function of temperature is measured. The observation of well resolved Mn2+ spectrum at room te mperature has been interpreted in terms of a narrowing mechanism calle d ''host spin-lattice relaxation narrowing''. (C) 1998 Elsevier Scienc e B.V. All rights reserved.