[On the polymorphism of barbiturates in powders and tablets. Part 2: On the infrared spectroscopy and the X-ray diffractometry of barbital (author's transl)].

By means of IR spectroscopy and X-ray diffractometry, two commercial brands of barbital and four barbital substances recrystallized from water or an acetone-water mixture were examined for polymorphism. The results obtained demonstrate that these substances differ in crystal lattice and that there are six polymorphic modifications.