Advancing ¹⁹F NMR Prediction of Metal-Fluoride Complexes in Solution: Insights from Ab Initio Molecular Dynamics

Abstract

¹⁹F NMR parameters are versatile probes for studying metal-fluoride complexes. Quantum chemical calculations of ¹⁹F NMR chemical shifts enhance the accuracy and validity of the resonance signal assignments in complex spectra. However, the treatment of solvation effects in these calculations remains challenging. In this study, we establish a successful computational protocol using ab initio molecular dynamics simulations for the accurate prediction of ¹⁹F NMR chemical shifts in square-planar nickel-fluoride complexes. In particular, we have studied in detail the trans-[NiF(2,3,4,5-C₆F₄I)(PEt₃)₂] complex in a benzene solution. Our computations revealed that accounting for the dynamic conformational flexibility of the complex, including intramolecular interactions, is crucial for obtaining reliable ¹⁹F NMR chemical shifts. Overall, this study advances the understanding of employing state-of-the-art quantum chemistry methods to accurately model ¹⁹F NMR chemical shifts of nickel-fluoride complexes, emphasizing the importance of addressing solvation effects in such calculations.