Towards accurate modelling of 1H NMR spectra of ionic liquids: The case of [C4mim][BF4] and its aqueous mixtures

Sipavičius, Einaras;Majauskaitė, Greta;Lengvinaitė, Dovilė;Bielskutė, Stasė;Klimavicius, Vytautas;Mocci, Francesca;Laaksonen, Aatto;Aidas, Kęstutis

2025-01-01

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Abstract

1H NMR spectra of neat [C4mim][BF4] and its aqueous mixtures have been computed with the near-quantitative accuracy for the first time, with root-mean square deviation of 0.2 ppm with respect to the measured spectra. The computational approach is based on classical MD simulations and linear-response quantum mechanics/molecular mechanics models. Theoretical predictions confirm that H NMR spectrum of imidazolium cations is virtually independent of the composition of aqueous ionic liquid mixtures, despite considerable changes to the structure of the first solvation shell around the imidazolium ring induced by the increasing content of water were observed.