Lewis-Acid Properties of Technetium(VII) Dioxide Trifluoride, TcO2F3: Characterization by 19F,17O, and 99Tc NMR Spectroscopy and Raman Spectroscopy,Density Functional Theory Calculations of TcO2F3,M+TcO2 F4- [M = Li, Cs, N(CH3)4], and

Technetium(VII) dioxide trifluoride. TcO2F3, behaves as a Lewis acid toward the fluoride ion and acetonitrile forming M⁺TcO2F4^- IM = Li, Cs, N(CH3)4] salts and TcO2F3·CH3CN. Fluorine-19 NMR spectroscopy established that the TcO2F4^- anion has a cis-dioxo geometry in CH3CN solution. Variable-temperature ¹⁹F NMR studies of TcO2F4^- and TcO2F3·CH3CN in CH3CN revealed that the one-bond couplings between ⁹⁹Tc and the two fluorine environments exhibit …