Crystal structure of tris[(4,7,13,16,21,24-hexa-oxa-1,10-di-aza-bicyclo-[8.8.8]hexa-cosane-κ(8)N2,O6)rubidium] rubidium nona-stannide.

The crystal structure of the title compound, [Rb(C18H36N2O6)]3RbSn9, consists of deltahedral [Sn9](4-) cluster anions, Rb(+) cations and cryptand mol-ecules, which partially sequester the cations. Those cations, which are not coordinated by cryptand mol-ecules, are neighboured directly to the [Sn9](4-) clusters and inter-connect them to form ∞(1)[RbSn9](3-) chains. These chains extend parallel to [001] and are arranged in a pseudo-hexa-gonal rod packing, separated by the Rb-cryptand complex cations.