基金This work was supported by the National Natural Science Foundation of China (No.20776089) and the New Century Excellent Talents Program of Ministry of Education (No.NCET-05-0783). The State Key Laboratory of Polymer Materials Engineering in Sichuan University was acknowledged for providing dmol3 modules and Prof. Ying Xue, Xiang-yuan Li, and Quan Zhu were grateful for the useful discussions.
基金Supported by Doctoral Startup Foundation of Anhui University(grant no.10113190077)the Anhui Provincial Natural Science Foundation(grant no.1608085QB39)the National Natural Science Foundation of China(grant no.51402001)