Kirkwood-Buff integrals and structure factor for binary mixtures of ionic liquid with 1-alkanol

Abstract

In this paper, we have tried to describe the factors affecting molecular interactions and structure of binary systems including 1-Hexyl-3-methylimidazolium Nitrate ([Hmim][NO3]) and 1-alkanol (1-hexanol, up to 1-decanol) using Kirkwood-Buff (KB) integrals and structure factor. Obtained results indicate that unlike molecules tend to form favorable interactions via forming hydrogen bonds or dipolar interactions and stay alongside, while an increase in the carbon chain of 1-alkanols reduces the strength of bonds and tendency of the unlike molecules to stay together. Moreover, the structure of mixtures was studied using the concentration-concentration structure factor, SCC(0). Results from the application of this parameter show that in all binary mixtures, heterocoordination is predominant, ordering occurs in solutions and fluctuations are less than random orientation. In addition, the chemical short-range order parameter α′, which is an important function to understand the complex formation and phase segregation in the liquid mixtures, was calculated and discussed for mentioned mixtures. For current binary mixtures, experimental data and theoretical investigations are novel and reported for the first time.