Quantitative structure–property relationship analysis of the spectrochemical series by employing electronic descriptors from DFT calculations

Correlations among Shimura’s parameter (d_Co) from spectrochemical series for 34 ligands and electronic descriptors from density functional theory calculations are reported. Simple and multiple linear regression models were constructed. The best results were obtained with the descriptors estimated with MN15 functional, obtaining a multiple linear regression model based on a quantitative structure–property relationship (QSPR) approach, with four attributes and the statistical parameters: R ² = 0.8543, Q²_LOO = 0.8050, and Q²_LMO = 0.7977. The four molecular descriptors are ligand field splitting (Δ), dipole moment (χ_C), enthalpy of the metal complex (H_C) and the ligand HOMO energy (E_{HO_L}). This model obtained for the Ni(0) complexes represents a novel approach to the spectroscopic series description based on computational tools also revising the models proposed from Werner’s description until modern recompilations carried out across the spectroscopic series developments. The applicability of the model was evaluated on cooper complexes and good prediction of the d_Co values for some ligands was also obtained.