Fine structure of energy levels and electron paramagnetic resonance parameters of Ni2+ doped in CsCdCl3

Complete diagonalization method (CDM) and high-order perturbation method (PTM) with forth-order formulae have been used to explain the optical spectra and ground term 3A2g electron paramagnetic resonance (EPR) parameters g//, g⊥ and zero-field splitting (ZFS) parameter D of Ni2+-doped CsCdCl3 within the framework of molecular orbital (MO) scheme, the calculated results are in good agreement with the experimental data. The trigonal parametersv and v′, Reach parameters B and C and the local defect structure are determined. The effect of vibronic interaction on optical spectra of 3T2g and 3A2g transition has been discussed with a1g and eg vibronic models, and the Huang–Phys parameters and vibronic coupling constant are evaluated.