Two previously unreported Ti3+ paramagnetic centres were observed in zircon, and were studied by means of X-band electron paramagnetic resonance at about 10K. The first of them was shown to arise from a Ti3+ electron-trap centre where Ti was substituted at one of the Si4+ sites (¯42m, D2d) of the tetragonal crystal. A full spin-Hamiltonian analysis of the centre was made. The second centre arose from Ti3+ which substituted for Zr4+ in the lattice and interacted with a 100% spin I = ½ nucleus (probably 31P) on a nearby lattice site which was thought to be a next-nearest neighbour Si site. The point-group symmetry of the site for this centre was 2(C2).

Two Ti3+ Centres Studied by X-Band Electron Paramagnetic Resonance at 10K in Zircon. R.F.C.Claridge, N.S.Lees, W.C.Tennant, C.J.Walsby: Journal of Physics - Condensed Matter, 1999, 11[17], 3571-80