ANALYSIS OF THE VIBRATION-SPECTRA OF 3,3' -THIODIPROPIONIC ACID AND ITS ALKALINE-SALTS

The Raman and infrared spectra of 3,3'-thiodipropionic acid and its po tassium salts in aqueous solution were recorded from 4000 to 200 cm(-1 ). An assignment of the fundamental vibrations is proposed. Analysis o f the polarization of the Raman lines indicated that the acid, the aci d salt and the neutral salt belong to the C-s symmetry group, On the b asis of the intermolecular hydrogen bond present iu the crystalline st ate of the acid salts, the potassium and sodium 3,3'-thiodipropionate acids can be classified as type A and B structures, respectively, acco rding to Speakman.