1. Department of Inorganic MaterialsCollege of ChemistryChemical Engineering and Materials ScienceSoochow University 199 Renai road Suzhou, Jiangsu Province 215123 PR China
2. Laboratoire de Recherche en Matériaux et Micro-spectroscopies Raman et FTIRUniversité de Moncton- Campus de Shippagan Shippagan, NB E8 S1P6 Canada
3. Laboratoire of Inorganic Materials ChemistryUniversity of Namur 61 rue de Bruxelles B-5000 Namur Belgium.