Molecular Modeling of Vanadium−Oxo Complexes. A Comparison of Quantum and Classical Methods

Abstract

A force field for vanadium-oxos was developed and tested with a variety of complexes with coordination numbers of 5 or 6 and formal oxidations states of +4 or +5 on the metal. Similarly, a semiempirical quantum mechanical method for transition metals was extended to vanadium. In this research soft and hard ligands were studied, as were ligands coordinated through single, multiple, and dative bonds. Despite the diversity of vanadium coordination chemistry, generally good modeling is achieved in a fraction of the time with less computational resources using molecular mechanics and semiempirical quantum mechanics. The L 4 V 4+ O and L 5 V 5+ O groups were emphasized given their prevalence and importance. In general, the predictive ability was superior for the former structural motif. The combination of molecular mechanics and semiempirical quantum calculations provide an effective and efficient tool for analysis of the steric and electronic energy differences between isomers.

PM3(tm) parameterization using genetic algorithms

“…The initial Tc parameters (i.e., those for generation zero) were obtained by interpolation of parameters for the metals flanking it in the periodic table—molybdenum and ruthenium (Table II). This method was found to be effective for vanadium 21.…”

Antidiabetic Bis-Maltolato-OxoVanadium(IV): Conversion of inactive trans- to bioactive cis-BMOV for possible binding to target PTP-1B

“…Applying the adapted Tripos FF (Tripos Inc.), the geometric structures of the BMOV and of some related complexes (Cundari et al 1997, 1998) were predicted correctly (Table 1). Prior to the unbiased docking of BMOV into the PTP-1B targets (PDB codes: 1bzc, 1bzh) (Groves et al 1998), the ligands were removed.…”

“…In general, vanadium compounds possess a higher diversity in their oxidation states as in their geometry. Cundari and colleagues had already demonstrated good modeling accuracy using semiempirical quantum chemistry and even molecular mechanics MM2 force fields (Cundari et al 1997, 1998). Other authors applied quantum chemical methods (Zborowski et al 2005).…”

Advances and Challenges in the Molecular Characterization of Petroporphyrins

“…The first study to implement a quantum mechanical approach by Cundari et al 136 is also the first to consider vanadyl porphyrins. In their work, the authors used molecular mechanics and both semiempirical and Hartree-Fock methodologies to predict the structures of vanadium oxo-complexes that were consistent with experimental structures and provide stretching parameters for V-O and V-N bonds for several vanadium oxidation degrees and oxygen compositions.…”