Popis: |
The spin-Hamiltonian coefficients for Fe3+ in sapphire have been redetermined by the classical paramagnetic resonance method. The value of g is 2.0026±0.0005 and is independent of temperature. The other coefficients, in units of 10-4 cm-1, and for temperatures of 4, 80 and 299 °K respectively, are: D = +1719.2, 1718.2, 1678.5; a = +229.4, 236.4, 229.1; F = -112.1, 101.3, 100.8 (D and a,±1 unit; F,±2 units). The paramagnetic resonance lines are consistent with the spin Hamiltonian to within the experimental error of 2 gauss. The zero-field splitting frequencies, measured directly, are, for 4, 80 and 299 °K respectively: ν(5/2, 3/2) = 19 281, 19 288, 18 850; ν(3/2, 1/2) = 12 037, 12 029, 11 741 Mc/s (all±0.05%). These frequencies are consistent with the spin Hamiltonian using the above coefficients. It is concluded that the spin Hamiltonian is valid within the above limits of error for fields from zero to 10 000 gauss. |