Hydrogen Bond Studies. XXXVII. The Crystal Structure of Sulfuric Acid Dihydrate (H3O+)2SO42−

Abstract

The crystal structure of H2SO4·2H2O has been determined from three-dimensional single-crystal x-ray data recorded at −190°C. The crystals are monoclinic, space group C2 / c, with 12 formula units in a cell with the dimensions: a = 13.008, b = 7.979, c = 14.881, and β = 101.60°. The structure consists of H3O+ and SO42− ions. Each of the three independent H3O+ ions is hydrogen bonded to three different SO42− ions (0···0 distances, 2.520–2.590 Å) is such a way that a three-dimensional hydrogen-bond pattern is formed. The average S–O distance in the sulfate ion is 1.474 Å.