Dissymmetrization in X-irradiated RbTiOPO4 crystal

Electron paramagnetic resonance has been used to study the hole and electro n paramagnetic centers formed in X-irradiated RbTiOPO4, the crystals of the KTP family. X-irradiation of RbTiOPO4 crystals at 77 K produced an oxygen hole center and four different trivalent titanium electron centers I-1, II, III and IV. The g-tensors, their principal values and axes for the defects were calculated and compared with those for KTiOPO4 centers. X-irradiation at 300 K produced another two oxygen hole centers and three electron cente rs I-1, I-2 and II. EPR spectra of the center II revealed dissymmetrization , i.e., irregular distribution of growth defects, between the physically eq uivalent sites lowering the point group symmetry of the local environment o f paramagnetic centers Ti3+.