A d1 Ti3+ center which was created by the X-irradiation of a synthetic zircon monocrystal at 77K was studied by using electron paramagnetic resonance techniques at 10K. The Ti3+ ion occupied a substitutional site with the point group symmetry, 4¯2m (D2d). The absence of both site-splitting in general crystal orientations, and of a superhyperfine structure from a +1 ion, indicated that no nearby charge compensator was involved. A comparison with electron paramagnetic resonance measurements of Ti3+ -quartz centers, point-charge calculations and 29Si hyperfine splittings indicated that the Ti3+ center resulted from electron capture by Ti4+ which occupied a Zr4+ site in the crystal. A center of the form, [TiO8]-, was suggested. Precise spin-Hamiltonian parameters, including 47Ti (l = 5/2, 7.4%) and 49Ti (l = 7/2, 5.4%) hyperfine, nuclear electric quadrupole and nuclear Zeeman parameter matrices, together with high-spin nuclear terms, were determined.

R.F.C.Claridge, D.G.McGavin, W.C.Tennant: Journal of Physics - Condensed Matter, 1995, 7[47], 9049-60