| dc.description |
Similar to the case of the spin-lattice coupling coefficients G<sub>ij</sub> in cubic symmetry, in this paper the simple correlations between the coupling coefficients F<sub>ij</sub>(F<sub>11</sub>, F<sub>12</sub> and F<sub>44</sub>) in a cubic field and the g-factor in cubic and low symmetries have been established, and hence a simple and uniform method suitable for calculating the coefficients F<sub>ij</sub> for all d<sup>n</sup> ions is given. As an example, the analytic expressions for F<sub>ij</sub> for d<sup>3</sup> ions in a cubic field are obtained from the high-order perturbation formulae for the g-factor. From these expressions, the coefficients F<sub>ij</sub> for MgO:Cr<sup>3+</sup> crystals have been calculated. The results are close to the experimental values and the errors are, as in the case of G<sub>ij</sub>, attributed mainly to the fact that the local elastic constants s<sub>ij</sub> in the vicinity of impurity ions are different from the host values. The coefficients F<sub>ij</sub> for MgO:V<sup>2+</sup> crystals, in which the local values are very similar to the bulk values, are also predicted. The results should be, as shown for the coefficients G<sub>ij</sub>, closer to the experimental values calculated from the bulk elastic constants. This point remains to be verified. |
