INFRARED STUDY OF SOLIDS AND CAST FILMS OF LONG-CHAIN FATTY-ACIDS

Infrared spectra have been measured for five long-chain fatty acids (C H3(CH2)n COOH; n = 14-18) in solid states, KBr discs and cast films. T he acids with even- and odd-numbered carbon atoms show structural diff erences, not only in the solid states but also in the cast films. For example, the molecular orientation of the hydrocarbon chains and the d irections of a and b axes of the orthorhombic subcell in the cast film s on Au-evaporated glass slides are different in the even-numbered and the odd-numbered acids.