The crystal and molecular structure of certain dicarboxylic acids. Part IV. β-succinic acid

Abstract

The parameters of the β-succinic acid crystal structure have been re-determined with the use of more complete Fourier series and the preparation of a new projection of the structure along the [101] crystal axis. Small shifts in the atomic positions are obtained, but the slight shortening of the carbon-carbon bonds below the standard value of 1·54 A. reported by Verweel and MacGillavry is confirmed. The present results indicate, however, that the shortest bond (1-50 A.) is that between the central pair of carbon atoms. The situation of this bond is similar to that of the central bond in dibenzyl and to that of the bond in geranylamine hydrochloride which is situated centrally between the two ethylene linkages. In both these cases a similar contraction has been observed. The intermolecular approach distances in the succinic acid structure are also discussed.