Theoretical computation of interaction parameters for the complexation of GSH with Pr(III) and Mg(II) in solution: Analysis of their reaction dynamics and thermodynamic characters

The current research focuses on the computation of absorption spectral parameters like energy interaction parameters viz. Slater-Condon factor (F_k), Racah (E^k), Lande spin-orbit interaction (ζ_4f), nephelauxetic ratio (β), bonding parameter (b^1/2), per cent covalency (δ), and the intensity parameters like oscillator strength (P) and Judd-Ofelt T_λ, (λ ​= ​2,4,6) parameters, of Pr³⁺ ion complexes with reduced Glutathione (GSH) in the presence and absence of Mg²⁺ in different aqueous solutions of CH₃OH, C₄H₈O₂, CH₃CN and DMF. The variations in the values of the energy interaction and intensity parameters clearly demonstrates the relative sensitivity of the 4f-4f transitions and its correlation with ligand structure and the nature of metal-ligand interaction. Further, the reaction dynamics and thermodynamic properties for the complexation of Pr³⁺ with glutathione and Mg²⁺ ligand have been investigated using different computed parameters like rate constant (k), activation energy (E_a), A (pre-exponential factor) and thermodynamic parameters, ΔH⁰, ΔG⁰ and ΔS⁰.