1. Key Laboratory of Macrocyclic and Supramolecular Chemistry of Guizhou Province, Guizhou University, Guiyang 550025, P. R. China
2. College of Chemistry and Chemical Engineering, Anhui University of Technology, Maanshan 243002, P. R. China
3. CSIRO Mineral Resources, PO Box 218, Lindfield, NSW 2070, Australia
4. Department of Chemistry, University of Hull, Hull HU6 7RX, UK