1. College of Chemistry and Materials Science Fujian Provincial Key Laboratory of Polymer Materials Fujian Normal University Fuzhou 350007 P. R. China
2. State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou Fujian 350002 P. R. China
3. Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology Wuhan 430074 P. R. China