Structural and dynamical analysis of ionic liquids in electric fields

Molecular rotors and molecular dynamics simulations are used to study changes in the structure and dynamics of ionic liquids in the presence of external electric fields. The immediate environment around the rotors is elucidated in the absence of the electric field from a study of the behaviour of the dyes in various ionic liquids. Using this knowledge, the effect of an electrode upon an ionic liquid at various depths was investigated by studying the change in the rotor properties upon application of a potential. This showed remarkable effects of an electrode upon the rotor properties up to 50 micrometres away from the electrode which persisted for over one hour. To attempt to rationalise these results, molecular dynamics simulations were performed on two ionic liquids in electric fields, and their structure and dynamics were studied over a range of electric fields. Particular focus was put onto the charge arm concept, as a replacement for the dipole in an ion. This was able to rationalise changes in the structure of the ion that were difficult to explain otherwise, such as changes to the conformation and rotation of the ions.Open Acces