Abstract:
Based on the crystal field theory, the anisotropic g factors
gii and the hyperfine structure constants
Aii for (NH
4)
2Mg(SO
4)
2·6H
2O:Cu
2+ are theoretically investigated by using the high-order perturbation formulas of these electron paramagnetic resonance (EPR) parameters for a 3d
9 ion in rhombically (
C4v) elongated octahedra. In the calculated formulas, the crystal field parameters are set up from the superposition model and the admixture of
d-orbitals in the ground state wave function is taken into account. According to the calculations, the local structure values Cu(H
2O)
62+ clustering in (NH
4)
2Mg(SO
4)
2·6H
2O crystal are:
Rx≈0.1872 nm,
Ry≈0.2033 nm,
Rz≈0.2292 nm; and the mixing coefficients of the ground state wave function parameters
α and
β are 0.995 and 0.0999, respectively. The calculated results show good agreement with the experimental data, and the reasonableness of these results is discussed.