Effect of ether functionalization and alkyl chain length on the structure and electronic properties of ammonium ionic liquids

The effect of alkyl chain length and ether functionalization on the geometrical and electronic structures of the ammonium-based ionic liquids was studied by density functional theory calculations. The magnitude of the cation–anion interaction energy decreases with increasing side-chain length. The interaction between cations and the chloride anion in the most stable conformers was investigated using the Natural Bond Orbital and Non-Covalent Interaction analyses. The molecular electrostatic potential maps were used to find favorable interaction sites of cations. Moreover, the standard heats of formation were evaluated by combining G3(MP2) theory calculations with the atomization reaction approach.