Incorporation of Manganese (II) in Beta-Tricalcium Phosphate from EPR and ENDOR Measurements for Powders

Powders of ?-tricalcium phosphate (?-TCP, Ca3PO4) doped with manganese (Mn2+) are comprehensively analyzed electron paramagnetic resonance (EPR) and electron-nuclear double (ENDOR) techniques. The modeling the spectra permitted to calculate values zero-field splitting (B20 = ?904 MHz; B40 ?1.41 MHz B43 195.2 MHz) explain origin low-field hyperfine structures as allowed spin transitions fine structure. Three structurally inequivalent positions for Mn2+ in ?-TCP crystal lattice identified their g-factors constants quantified. obtained results can serve fundamental background study disordered matrices high (S ? 1) impurities which important catalytic systems.