Bleaching the Record: After 200 Years, Single Crystal X-Ray Crystallography Reveals the Structure and Hydrogen-Bonding Properties of Hypochlorite and Hypobromite Ions in the Solid State

Abstract

<div>We report the first single crystal structures of hypochlorite and hypobromite salts, including hydrated sodium hypochlorite - a ubiquitous bleaching and disinfection agent in use for almost 200 years. The structures represent the first characterization of fundamentally important hypochlorite and hypobromite anions in the solid state, by X-ray crystallography and are supported by Raman spectroscopy on individual crystals. The structural analysis provides insight into supramolecular chemistry of the hypohalite ions in the hydrated environment of the NaOCl<sup>.</sup>5H<sub>2</sub>O and NaOBr<sup>.</sup>5H<sub>2</sub>O solid salts, and reveals measured Cl-O and Br-O bond lengths of 1.69 A and 1.82 A, respectively, which are significantly longer than those for corresponding higher-valence oxoanions, and in agreement with the values spectroscopically determined for hypohalous acids and corresponding oxides in the gas phase.<br></div>