Understanding the microscopic structural organization of neat ammonium based ionic liquids through resonance energy transfer (RET) studies

The present work aims at understanding the role of chemical structure of a cationic moiety of a given ionic liquid (IL) on the overall structural organization of the same IL in its fluid state through resonance energy transfer studies (RET). For this purpose, two branched alkyl group containing (butyl and octyl) ILs and one single alkyl chain (butyl) containing (non-branched) IL have been employed. During RET studies, neat ammonium-based ILs have been used as the donor and a charged solute rhodamine 6 G (R6G) as an acceptor as they satisfy the spectroscopic criteria needed for RET event to occur. The outcome of the present investigation depicts a more favorable RET interaction for a non-branched IL in comparison to that for branched ILs. The data has been explained by considering both electronic and steric effects. The current investigation illustrates that the structural organization of non- branched ILs are different from that of branched ILs.

Automated summary

The study aimed to understand the impact of the chemical structure of a cationic moiety in an ionic liquid on its overall structural organization in the fluid state through resonance energy transfer studies. Non-branched ILs showed a more favorable RET interaction compared to branched ILs, with the difference attributed to both electronic and steric effects.