Cesium Hydroperoxostannate: First Complete Structural Characterization of a Homoleptic Hydroperoxocomplex

The crystal structure of cesium hexahydroperoxostannate Cs2Sn(OOH)6 is presented. The compound was characterized by single crystal and by powder X-ray diffraction, FTIR, 119Sn MAS NMR, and TG-DTA. Cs2Sn(OOH)6 crystallizes in the trigonal space group P3̅, a = 7.5575(4), c = 5.1050(6) Å, V = 252.51(4) Å3, Z = 1, R1 = 0.0120 (I > 2σ(I)), wR2 = 0.0293 (all data), and comprises cesium cations and slightly distorted octahedral [Sn(OOH)6]2− anions lying on the threefold axis. The [Sn(OOH)6]2− unit forms 12 interanion hydrogen bonds resulting in anionic chains spread along the c-axis. All six hydroperoxo ligands are crystallographically equivalent; O−O distances are 1.482(2), only slightly longer than the O−O distance in hydrogen peroxide. FTIR and 119Sn MAS NMR reveal the similarity between all alkali hydroperoxostannates.