Quantum Chemical Study on Structure Properties of Pyridine Ionic Liquids of Different Chain Lengths Substituent Group

Abstract

By using density functional theory (DFT) at B3LYP/6-31G* levels, the pyridine ionic liquid with different substituent length have been studied. The calculated results showed that the ionic liquid formed by pyridine and a chlorine ion has two main configurations (COH-PyCl and COH-PyPCl). There are three combinative locations in each configuration of anion and cation. When the anion is located in the same location, as the alkyl length becomes longer, the hydrogen bond length between chlorine ion and hydrogen atom in pyridine ring becomes longer, the binding energy between chlorine ion and pyridine with different alkyl length becomes weaker.