摘要
The Hartree-Fock method has been employed to investigate the electronic structures of EMIM＋（1- ethyl-3-methylimidazolium＋）, AlCl4^-, and EMIM＋-AlCl4^-. Full optimization and frequency analyses of EMIM＋, AlCl4^-, ten initial EMIM＋-AlCl4^- geometries have been carried out using the Gaussian-94 soft-package at 6- 31＋G（d,p） basis set level for hydrogen, carbon, nitrogen, chlorine, and aluminum atoms. The electronic structures of the lowest energy of EMIM＋-AlCl4^-pairs, single EMIM^＋, and AlCl4^- have been comparatively studied. The calculated results showed that the optimized EMIM^＋-AlCl4^-pair conformer of lowest energy was AlCl4^-outside the five-ring plane between methyl group and ethyl group with a H6--C122 distance of 2.7 A. The frequency analyses suggested that all stationary points were minimum points because of no imaginary frequency appearing, and the assigned frequencies were in agreement with experimental report. The interaction energy between EMIM^＋ and AlCl4^-was 776.2 kJ/mol.
