Temperature Dependencies of 19 F NMR Spectra Parameters in BF 4? Solutions

Abstract

Despite numerous studies on the BF₄ ⁻ anion ^1-6 indicating to its complex behavior in different solutions in the presence of different cations, it is still quite difficult to explain this unambiguously. This is ostensibly due to the incompleteness of experimental data both for temperature dependencies and for solution compositions³. Taking this into account, we measured the dependencies of ¹⁹F NMR spectra in a broad range of temperatures and concentrations in aqueous and water-acetone solutions of Co²⁺, Ni²⁺ and Zn²⁺ tetrafluoroborate salts on “RYA-2305” and “SWL 2-31/10” instruments in spherical and cylindrical ampoules. The said dependencies were recorded both for BF₄ ⁻ and BF₃OH⁻ signals, the latter forming in insignificant quantities due to the hydrolysis of the tetrafluoroborate anion in positively hydrated cation solutions¹.