Synthesis and Computational Elucidation of a New Dipicolinato-Vanadium(V) Complex: Crystal Structure, Hirsfeld Surface, FMO, MEP, and NCI Studies

Abstract: A new vanadium (V) complex [VO(dipic)(hpo)(H₂O)] (1) (where “dipic” is dipicolinate and hpo is 1-(2-hydroxyphenyl)ethanone oxime) is synthesized with a oxime moiety and dipicolinato anion as ligands. Using single crystal X-ray diffraction technique, the structure of the complex 1 is determined. The theoretically optimized structure of the complex is obtained from DFT calculations predicting a distorted pentagonal-bipyramidal geometry. Theoretically predicted structure is in excellent match with the experimentally obtained structure utilizing X-ray single crystal diffraction analysis. Frontier molecular orbital (FMO) analysis, molecular electrostatic potential (MEP) are performed to understand the stability and reactivity characteristics of the complex. The simulated UV-Vis maximum absorption wavelength from TDDFT method is in excellent agreement with the experimentally observed λ_max. Hirshfeld surface analysis indicates hydrogen bonding involving O–HO interactions play major role in stabilizing the molecular crystal. Interesting non-covalent interactions are revealed by a thorough examination of the complex’s solid state architecture. In the solid state, strong self-assembled complex formation is dependent on hydrogen bonding interactions, V⋯O, and V⋯N interactions.