Theoretical Studies of Vanadium Complexes: Reactivities and 51V NMR Chemical Shifts in Solution
We present a density functional study of structures and reactivities of [VO(O2)2(Im)]−, a model peroxovanadium(V) complex with a biogenic ligand, and its potential use as catalyst in biomimetic oxidations of organic substrates. The mechanism of olefin epoxidation mediated by this complex is studied in detail for the gas-phase. In addition, structures and energetics of key intermediates in the catalytic cycle are simulated in solution using the Car-Parrinello molecular dynamics (CPMD) technique. The rate-limiting step is indicated to be oxo transfer from a peroxo moiety of the catalyst to the substrate. In a second part, the standard used for 51V NMR spectroscopy, VOCl3, is modeled as neat liquid by means of CPMD simulations. According to preliminary results for the magnetic shieldings averaged along the trajectory, the 51V nucleus is deshielded by ca. 40 ppm.
KeywordsElectronic Structure Calculation Transient Absorption Spectrum Semiconductor Interface Quantum Dissipative System Bath Mode
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