Seven spin-Hamiltonian parameters (g factors g // , g ⊥ and zero-field splittings b20, b40, b44, b60, b64) of two tetragonal Gd 3+ centers, denoted A and B, in layered perovskite fluoride Tl 2 ZnF 4 crystals doped only with Gd 3+ ion and co-doped with Gd 3+ and Li + are calculated using the diagonalization (of energy matrix) method based on the one-electron crystal-field mechanism. In the calculations, the defect models suggested in the previous paper that center A is due to Gd 3+ ion at the octahedral Zn 2+ site without any local charge compensation and center B is due to Gd 3+ ion at the nine-coordinated Tl 2+ site associated with a Li + ion at the nearest Zn 2+ site along C 4 axis for charge compensation are applied. The calculated results are in reasonable agreement with the experimental values. The suggested defect models of both Gd 3+ centers are therefore confirmed and the respective defect structural data are obtained. The results, including the validity of defect structural data, are discussed.