Analysis of electron paramagnetic resonance and optical studies of central metal ion (Cu2+) in lithium potassium phthalate single crystal

Molecular ion Cu2+ in lithium potassium phthalate (LiKP) single crystal has been grown at room temperature by slow evaporation process. Single crystal EPR study has been taken for the LiKP:Cu2+ crystal. Presence of two Cu2+ sites is reported from EPR data. Angular variation plot in the three planes is used to determine the principal g and A values. Spin Hamiltonian parameter values reveal that site A and site B exist as orthorhombic and axial crystal field symmetry around the impurity ion. Substitutional incorporation has occurred for site A and site B exists as interstitial position in the LiKP:Cu2+ crystal lattice. Using admixture coefficient terms, the ground state of the grown crystal has been calculated. Molecular orbital coefficients have been obtained from the principal g and A values. Optical absorption study was carried out at room temperature. Through optical absorption data, D-q, D-s, and D-t parameters have been evaluated, showing the tetragonally distorted octahedral symmetry of Cu2+ ion in LiKP lattice.