Jm. Gaite et H. Rager, ELECTRON-PARAMAGNETIC-RESONANCE STUDY OF FE3-1 POSITION IN FORSTERITE( AT M), Journal of physics. Condensed matter, 9(45), 1997, pp. 10033-10039
In an electron paramagnetic resonance study of a synthetic single crys
tal of forsterite, Mg2SiO4, one spectrum of Fe3+ with maximum local sy
mmetry -1 was observed. This spectrum arises from Fe3+ substituted for
Mg2+ at the M-1 position. The second-order constants of the spectrum
are b(2)(0) = 0.184 cm(-1) and b(2)(2) = 0.1422 cm(-1). All the fourth
-order spin-Hamiltonian constants are given: they are much larger than
generally observed in silicates. The zero-field splitting of the EPR
spectrum is larger than the energy of the hyperfrequency field in the
Q band; this case is near the limit of possibility of calculating the
fourth-order constants of the spin Hamiltonian. It is shown that the s
ubstitution of Fe3+ for Mg2+ does not strongly modify the local struct
ure and that there is no local charge compensation.