Electron paramagnetic resonance study of at position in forsterite

Abstract

In an electron paramagnetic resonance study of a synthetic single crystal of forsterite, , one spectrum of with maximum local symmetry -1 was observed. This spectrum arises from substituted for at the position. The second-order constants of the spectrum are and . 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 substitution of for does not strongly modify the local structure and that there is no local charge compensation.