A group contribution method to predict the melting point of ionic liquids

The melting points of several families of ionic liquids were predicted with a simple group contribution method. A set of 200 ionic liquids was used to obtain the contributions for anion and cation groups. The optimum parameters of the method were obtained using a genetic algorithm-based on multivariate linear regression. Then, the melting temperatures of another 200 ionic liquids were predicted, and the results were compared with experimental data available in the literature. The study shows that the proposed group contribution method represents an excellent alternative for the estimation of the melting point of diverse ionic liquids from the knowledge of their molecular structure, with an average deviation of 7%.

► 200 ionic liquids were used to obtain the contributions for 36 anion groups and 31 cation groups.
► Optimum parameters were obtained by a genetic algorithm-based on multivariate linear regression.
► The results show an average deviation of 7% in the prediction of the melting point of several ionic liquids.