LAUSR

Abstract The effect of crystal-field Hamiltonian with cubic symmetry acting upon different angular momenta J-manifolds between 2 and 8 has been investigated considering the quantization axis along body diagonal [111] axis of the cube. The eigen-values and eigen-functions are numerically computed as a function of the ratio between the fourth and sixth degree terms of the cubic Hamiltonian, expressed in terms of the two parameters, e.g., x and W, in the notation of LLW [J. Phys. Chem. Solids 23 (1962) 1381]. The analytical expressions of eigen-values are also presented for few J values. The effect of external magnetic field as a perturbation on the crystal-field level scheme is discussed toward calculations of magnetic susceptibility and axial magnetizations and compared with the LLW Hamiltonian.