Die Hydrate von tert-Butanol : Kristallstruktur von Me3COH.2H2O und Me3COH.7H2

The system tert-butanol-water has been confirmed by X-ray powder diffraction and single-crystal structure analysis to contain two hydrates, a dihydrate and a higher hydrate. The composition of the latter, contradictory in the literature, could be resolved in favor of the new one of a heptahydrate. The dihydrate (m.p. 0.7 o C) is monoclinic with space group P2 1 and Z=2 formula units per unit cell of dimensions a=6.017, b=6.055, c=10.377 A and β=106.60 o at -150 o C. The heptahydrate (m.p. -6 o C, dec.) is orthorhombic with space group Pnma, Z=4, a=12.589, b=15.251 and c=6.645 A at -150 o C