The paramagnetic resonance spectrum of a monoclinic FeZn+(A-)-X complex with a 4A2(F) ground state was studied, under band-to-band illumination, in Fe-doped cubic crystals. The monoclinic distortion of the cubic crystal field was attributed to one or more associated defects, X, whose origin was unknown. The largest component of the distortion was oriented along a <100> axis. All of the transitions arose from a spin ground doublet |±½> which could be described by an effective spin Hamiltonian with S = ½. The g-values were gz = 2.223, gx = 4.426 and gy = 4.608, where x was [110] and y and z were inclined by 8.5º with respect to [¯110] and [001], respectively, in the plane which was perpendicular to x. The corresponding parameters of a spin Hamiltonian which described the full S = (3/2)d7 ground state manifold were gx = gy = 2.259, gz = 2.224 and E/D = 0.0134, with D greater than 1/cm.

J.Kreissl, B.Litzenburger, U.W.Pohl, W.Gehlhoff, H.E.Gumlich: Solid State Communications, 1995, 94[8], 667-72