Optical properties derived from the refractive index dispersion of alkyl-imidazolium based ionic liquids

Abstract

Ionic liquids are advanced materials with great potential to take part in optical applications such as optical imaging, ultrafast optics, laser technology and so on. In view of this, a precise knowledge of their optical behavior is necessary to ensure the optimal performance of a device. In this work, the chromatic dispersion of a set of alkyl-imidazolium-based ionic liquids is characterized in a quasi-continuous spectral interval comprising wavelengths between 400 and 1000 nm. A model based on the Sellmeier equation is fitted to the data; this model allows the identification of behaviors and trends related to the structure of the material or environmental conditions (temperature). The model is also used to calculate other dispersive magnitudes derived from the refractive index such as the Abbe number, group index, group velocity dispersion, third-order dispersion.