Single Crystal EPR Study of Mn(II)-Doped Biomineral: Cadmium Ammonium Phosphate Hexahydrate

Abstract

Single crystal Electron Paramagnetic Resonance studies on Mn(II) doped cadmium ammonium phosphate hexahydrate were carried out at room temperature. The angular variation spectra of the crystal in three orthogonal planes show that the paramagnetic impurity Mn(II) has entered the host lattice substitutionally. The spin Hamiltonian parameters calculated from the EPR data are g = 2.002, A = 9.25 mT, D = 32.7 mT, a = 0.3 mT and F = 0.6 mT. These Hamiltonian parameter values (g, A and D) match fairly well with those calculated from the powder spectrum. The percentage covalency of Mn-O bond has been estimated to be 8.5.

Single-crystal EPR investigation of Mn(II)-doped biomineral cobalt ammonium phosphate hexahydrate: a case of multiple substitutions

“…In addition, the unit cell contains two molecules and the central sextet shows abnormal intensity behavior. Similar observations have been reported, when Mn(II) ions are doped in cadmium ammonium phosphate hexahydrate single crystals [21]. Figure 2 contains an EPR spectrum of Mn(II)/CoAPH, corresponding to the minimum spread of the spectrum in the bc-plane, which roughly corresponds to the magic angle (see below).…”