The solvent effect of ionic liquids on CO₂ fixation catalyzed by hydroxyl-functionalized quaternary ammonium-based ionic liquids is thoroughly investigated by ONIOM method associated with the molecular dynamics simulation. As compared with the catalytic activity determined in experiment, the catalytic activity estimated by ONIOM model is more credible than previous result calculated by the polarized continuum model. The critical hydrogen bond and C-Br interaction are analyzed by non-covalent interaction and the atoms in molecules methods. The analysis indicates that the electrophilic activation aroused by hydrogen bond provides more contribution than nucleophilic activation aroused by C-Br interaction in reaction catalyzed by trihydroxyethylethyl ammonium bromide. In contrast, the nucleophilic activation is more important in reactions catalyzed by other three ionic liquids. Choice of the suitable model is possible to obtain the reliable catalytic activity, which would be comparable with the experimental result.

离子液体对CO ₂的溶剂作用结合分子动力学模拟，采用ONIOM方法对羟基官能化季铵盐基离子液体催化的固定化进行了深入研究。与实验确定的催化活性相比，ONIOM模型估算的催化活性比极化连续谱模型计算的先前结果更可信。通过非共价相互作用和分子中的原子方法分析了关键的氢键和C-Br相互作用。分析表明，在三羟乙基乙基溴化铵催化的反应中，氢键引起的亲电活化作用比C-Br相互作用引起的亲核活化作用更大。相反，在其他三种离子液体催化的反应中，亲核活化更为重要。