EPR and optical study of Mn²⁺ doped monohydrated dipotassium stannic chloride

Highlights: • EPR study of Mn²⁺: DPSC crystal is done at room temperature. • The spin Hamiltonian parameters for two Mn²⁺ sites are determined. • The optical absorption study is also done. • The nature of metal–ligand bonding is discussed on the basis of EPR and optical data. • Theoretical zero-field splitting parameters match well with the experimental values. - Abstract: Electron paramagnetic resonance (EPR) study at room temperature (RT) is used to investigate the property of Mn²⁺ doped monohydrated dipotassium stannic chloride (K₂SnCl₄⋅H₂O) single crystal. EPR spectra show that there exist two substitutional sites, the spin Hamiltonian parameters for which are determined. The optical absorption study is also done at room temperature in the wavelength range 195–1100 nm. The observed bands are assigned as transitions from ⁶A_1g(S) ground state to various excited states. These bands are fitted with four parameters, namely Racah inter-electronic repulsion parameters B = 792 cm⁻¹, C = 2278 cm⁻¹; cubic crystal field splitting parameter Dq = 700 cm⁻¹ and Trees correction α = 76 cm⁻¹. The nature of metal–ligand bonding is discussed on the basis of EPR and optical data. Superposition model (SPM) is used to find out the crystal field (CF) parameters and the perturbation formulae are used to obtain zero-field splitting (ZFS) parameters. Theoretically calculated ZFS parameters match well with the experimental values obtained from EPR study