Crystal structure of hexaaqua(isocyanurato-O)calcium isocyanurate monohydrate

Abstract

Crystals of [Ca(C₃H₂N₃O₃)(H₂O)₆]⁺ · (C₃H₂N₃O₃)⁻ · H₂O (I) are restudied by X-ray crystallography. The previous X-ray study is shown to be incorrect. The crystal structure of I (space group $P\bar 1$, a = 6.503 Å, b = 10.830 Å, c = 11.824 Å, α = 103.58°, β = 92.64°, γ = 98.82°, Z = 2) is solved by a direct method and refined by the full-matrix least-squares method in the anisotropic approximation to R = 0.037 for 2792 independent reflections (CAD4 automated diffractometer, λMoK _α radiation). In the [Ca(C₃H₂N₃O₃)(H₂O)₆]⁺ complex cation, the coordination polyhedron of the Ca atom is a strongly distorted octahedron with one additional vertex. The crystal of I contains a developed three-dimensional system of interionic (intermolecular) hydrogen bonds involving all H atoms.