RAMAN SPECTRAL STUDY ON ISOPOLYTUNGSTATES IN AQUEOUS SOLUTION  

作　　者：Liu, Shijun  Chen, Qiyuan  Zhang, Pingmin  Li, Songqin 

机构地区：[1] Central South Univ of Technology, Changsha, China

出　　处：《中国有色金属学会会刊：英文版》1998年第4期157-161,共5页Transactions of Nonferrous Metals Society of China

摘　　要：ＩＮＴＲＯＤＵＣＴＩＯＮＡｌａｒｇｅｎｕｍｂｅｒｏｆｓｔｕｄｉｅｓｈａｖｅｂｅｎｄｏｎｅｉｎｔｈｅｆｉｅｌｄｏｆｔｈｅａｑｕｅｏｕｓｃｈｅｍｉｓｔｒｙｏｆｉｓｏｐｏｌｙｔｕｎｇｓｔａｔｅｕｓｉｎｇｎｕｍｅｒｏｕｓｅｘｐｅｒｉｍｅｎｔａｌｍｅｔｈｏ...In the acidic aqueous Na 2WO 4 solutions in a range of Z (H +/WO 2- 4)=0～1.50, the chemical state of isopolytungstates has been studied using Raman spectroscopy. It was found that in the solution of Z ≤1.25, the dominant polynuclear species at any time is paratungstate A, W 7O 6- 24 , which also exists at Z = 1.42. During the aging of solution, paratungstate A is slowly transformed to paratungstate B, H 2W 12 O 10- 42 , which is easily deposited as the crystal Na 10 H 2W 12 O 42 ·27H 2O, but the concentration of paratungstate B in the solution is too low to be detected. In the solution of Z =1.42 and 1.50, there are probably metastable species, but metatungstate, H 2W 12 O 6- 40 , becomes the dominant species after long aging.

关 键 词：RAMAN SPECTRA isopolytungstate paratungstate metatungstate 

分 类 号：O657.37[理学—分析化学]