Conformational evolution of TFSI− in protic and aprotic ionic liquids
Journal article, 2011

We here report on the conformational evolution of the bis(trifluoromethanesulfonyl)imide anion (TFSI−) in protic and aprotic TFSI−-based ionic liquids as a function of temperature. The investigation is performed by Raman spectroscopy in the spectral ranges 240-380 cm−1 and 715-765 cm−1, where the interference from bands due to the cations is negligible. The contribution from each TFSI− conformation, i.e. the cisoid (C1) and the transoid (C2), is quantified in order to estimate the enthalpy of conformational change, ΔH, which is found to be in the range 3.4–7.3 kJ/mol in the liquid state. Conformational information is for the first time determined from the 740 cm−1 band, which previously mainly has been used as an indicator of ion-ion interactions. The similarity in ΔH values obtained from the two spectral ranges demonstrates the validity of using also the 740 cm−1 band for the quantification of the TFSI conformational evolution.

TFSI

Ionic liquids

Raman Spectroscopy

conformation

Author

Anna Martinelli

Chalmers, Applied Physics, Condensed Matter Physics

Aleksandar Matic

Chalmers, Applied Physics, Condensed Matter Physics

Patrik Johansson

Chalmers, Applied Physics, Condensed Matter Physics

Per Jacobsson

Chalmers, Applied Physics, Condensed Matter Physics

Lars Börjesson

Chalmers, Applied Physics, Condensed Matter Physics

Alessandra Fernicola

Stefania Panero

Bruno Scrosati

H. Ohno

Journal of Raman Spectroscopy

0377-0486 (ISSN) 1097-4555 (eISSN)

Driving Forces

Sustainable development

Subject Categories

Other Engineering and Technologies

Condensed Matter Physics

Areas of Advance

Energy

Materials Science

More information

Created

10/7/2017