The crystal structure of α‐succinic acid

The structure of the high‐temperature modification (α‐form) of succinic acid is not monoclinic as described in the literature, but triclinic. Its pseudo monoclinic habitus is caused by the formation of twins. The cell dimensions are determined. Although the atomic positions could not be determined exactly, it is shown that the structure of α‐succinic acid is closely related to that of adipic acid and the higher homologues of the series of even dibasic acids, and differs from those of both forms of oxalic acid and β‐succinic acid.