EPR and optical spectra of vanadyl doped Cadmium Ammonium Phosphate He
xa Hydrate (CAPH) are investigated both at room and liquid nitrogen te
mperatures. The results and analysis reveal that the site symmetry of
the VO2+ ion is tetragonal (C-4v). The following crystal field and spi
n Hamiltonian parameters are evaluated. Dq = 1600 cm(-1), Ds = - 3275
cm(-1) and Dt = 488 cm(-1), g parallel to = 1.931, g perpendicular to
= 1.993, A parallel to = 183 x 10(-4) cm(-1), A perpendicular to = 72
x 10(-4) cm(-1).