The Cation H_(13)O_6+: A Short, Symmetric Hydrogen Bond

The H_(13)O_6+ ion has been found to exist as a discrete entity, forming when the cage compound [(C_9H_(18)_3(NH)_2Cl]+Cl is crystallized from hydrochloric acid solution. The aquo-cation H_(13)O_6 has crystallographic symmetry 2/m (C_(2h)). The central bond O••H••O is symmetric, with a length of 2.39 ± 0.02 angstroms; the four outer hydrogen bonds are asymmetric, with a length of 2.52 ± 0.01 angstroms. The cage compound consists of a chloride ion encapsulated within a triply bridged diammonium species, with hydrogen bond distances N(H)••Cl of 3.10 ± 0.01 angstroms.