μ-Hexa­thio­metadiphosphato-bis­[(1,4,7,10,13,16-hexa­oxa­cyclo­octa­decane-κ(6) O)rubidium] aceto­nitrile disolvate

The asymmetric unit of the title compound, [Rb(2)(P(2)S(6))(C(12)H(24)O(6))(2)]·2CH(3)CN, contains one half of an [Rb(18-crown-6)(2)](2)[P(2)S(6)] unit and one aceto­nitrile solvent mol­ecule. The [Rb(18-crown-6)](2)[P(2)S(6)] unit is completed by inversion symmetry. Its Rb(+) ion is situated near the centre of the macrocyclic cavity, but is displaced by 0.8972 (1) Å from the O atoms of the crown in the direction of the [P(2)S(6)](2−) moiety. The overall coordination number of the cation is eight, defined by the six crown ether O atoms and by two terminal S atoms of the [P(2)S(6)](2−) anion. The hexa­thio­metadiphosphate anion is built up from two tetra­hedral PS(4) units joined together by a common edge. The crystal structure is characterized by alternating layers of [Rb(18-crown-6)](2)[P(2)S(6)] and aceto­nitrile solvent mol­ecules stacked along [010].