Hexa-kis-{[1-(dimethyl-amino)-propyl-idene]oxidanium} bis-(dodeca-molybdo-phosphate) N,N-dimethyl-propionamide penta-solvate.

In the asymmetric unit of the title salt, (C(5)H(12)NO)(6)[PMo(12)O(40)](2)·5C(5)H(11)NO, there are two independent α-Keggin-type [PMo(12)O(40)](3-) polyoxidoanions, which show characteristic features with respect to bond lengths and angles. One of the [CH(3)CH(2)C(=OH)N(CH(3))(2)](+) cations is hydrogen bonded to the neighboring polyoxidoanion through a C=O-H⋯O(bridge) hydrogen bond. The organic mol-ecules and the remaining organic cations form [(C(5)H(11)NO)(2)H](+) mol-ecule-cation pairs, two of which lie about inversion centers, through O-H⋯O hydrogen bonds.