Phloroglucitol Diammoniacate, C₆H₉(OH)₃.2NH₃

Abstract

THE determination of the crystal structure of phloroglucitol dihydrate, besides establishing the fact that the α-phloroglucitol molecule has the configuration x,x,x, shows that the water molecules are chiefly responsible for the cohesion of the organic molecules in the lattice¹. The structure is rhombohedral, and in the (111) planes equilateral triangles of hydroxylic oxygens are formed, each of the three oxygen atoms belonging to a separate phloroglucitol molecule. On the line perpendicular to the plane of the triangles and joining the centres of two triangles, two water molecules are situated ; and the distance from each water oxygen to the nearest three alcoholic oxygens and also the distance between the two water oxygen atoms is about 2·75 A. It is obvious, therefore, that the bonds linking together the group are hydrogen bonds.