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Updated: Mar 7, 2026
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Molecular Dynamics in Tetrafluoridoborate Salts of Divalent Metals Studied by Nuclear Magnetic Resonance Spectroscopy
Anton Gradišek1, Kristian Radan1, Matic Lozinšek1
1Jožef Stefan Institute, Ljubljana, Slovenia.
Abstract:
Fluoridoborate (BF4 -) salts are linchpins across synthesis and catalysis, key constituents of ionic liquids, and promising electrolytes and additives in next-generation multivalent rechargeable batteries. Despite this reach, quantitative links between crystal chemistry and anion motion remain scarce. Here, we present a molecular dynamics study of four such salts, namely M(BF4)2 (M = Ca2+, Sr2+, Ba2+, Cd2+), by means of nuclear magnetic resonance spectroscopy (NMR). We measured the temperature dependence of static 19F NMR spectra and spin-lattice relaxation and determined the values of activation energies for the thermally-activated reorientations for the BF4 - tetrahedra. We draw a comparison with systems with similar geometries, such as the well-studied complex metal borohydrides.
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