1,1,2,2-Tetrafluoro-2- (polyfluoroalkoxy )ethanesulfonic Acids, 1,1,2,2-Tetrafluoro-2- (perfluoroalkoxy )ethanesulfonic Acids, and 2,2'-Oxybis ( 1,1,2,2- tetrafluoroet hanesulfonic acid) By courtesy of: Wenbiao Cen, Zhi-Xia Dong, Ting-Ji Huang, Debao Su, and Jean’ne M. Shreeve* Inorg. Chem. 1988, 27, 1376-1377