CO2是著名的温室气体之一，能引发显著的温室效应。同时，CO2又是丰富、无毒的碳或者碳氧资源，将CO2转化利用可以同时解决环境污染和碳资源匮乏这两大难题。CO2与环氧化合物反应生成环状碳酸酯是化学固定CO2的方法之一，也是目前少数能进行工业化生产的途径。但是CO2中C处于最高氧化态难于活化，因此该反应需要在催化剂的作用下才能实现。开发高效、绿色的催化剂是实现CO2高效转化过程中一个亟待解决的问题。功能化离子液体是一类重要的催化剂，但是其反应机理尚不清楚，特别是以离子液体簇为催化剂的反应机理尚是空白。本项目拟采用理论计算方法研究功能化离子液体催化CO2转化的反应机理；包括单分子离子液体和离子液体簇为催化剂的反应机理，使模拟的环境更接近于真实的体系；采用分子动力学方法考察离子液体微观结构与宏观性能之间的关系；探索CO2转化的新途径；并设计新型的离子液体催化剂。

CO2 is one of the most famous greenhouse gas, which will greatly increase the temperature of earth's surface. Moreover, it can also be used as an abundant, inexpensive, and nontoxic carbon resource to produce useful organic compounds. Both problems of the pollution and scarcity of carbor resources will be solved if CO2 will be utilized and fixation. The cycloaddition of CO2 with epoxides to afford five-membered cyclic carbonates is one of the most widely applied technologies of the chemical fixation. However the carbon atom of CO2 is stable, the catalyst is necessary in the cycloaddition process. Thus, developing high-efficiency and environment friendly catalysts for this cycloaddition reaction is highly desirable. Functionalized ionic liquid is one class of novel efficient catalyst for chemical fixation of CO2 to cyclic carbonate. However, the details of the mechanism are still ambiguous and worthy of further exploration, especially for the reactions catalyzed by the ionic liquid cluster. We hope to cast light on the detailed mechanism theoretically; in particularly to explore the mechanism catalyzed by the ionic liquid cluster; to study the relationship between the microscopic structure and the macroscopic properties by molecular dynamics simulation; and to search for the new route of CO2 fixation. On the basis of these research the new ionic liquids will be theoretically designed.