Silver Hydrogen Sulfate, Ag(O3SOH): Preparation, and the OD Character of the Crystal Structure

Crystalline Ag(O 3 SOH) was produced by reacting Ag 2 O or silver sulfate with sulfuric acid. The crystals, which are stable only in an extremely dry atmosphere, show a X-ray diffraction pattern with apparent mmm symmetry, with extinction rules inconsistent with any space group and suggestive of the order−disorder (OD) character of the structure. In fact, the specimens studied are monoclinic polytypes, space group P 12 1 / c 1, a = 15.140(3) Å, b = 8.199(1) Å, c = 10.721(1) Å, β = 90.00(1)°, V = 1330.8(3) Å 3, Z = 16, of a whole OD family. The OD approach allowed a successful structure solution; the refinement [ R = 4.25%, R w = 9.37%, 1449 observed data F 0 > 4σ( F 0 )] showed four different silver ions having a highly distorted octahedral coordination. The mean Ag−O distance is 2.543 Å and one of the silver cations has a seventh oxygen atom at a distance of 2.84(1) Å. Silver hydrogen sulfate in sulfuric acid solution absorbs carbon monoxide reversibly.