Low-temperature phase of hexaguanidinium heptamolybdate monohydrate

Abstract

The crystal structure of the title compound, [C(NH2)3]6[Mo7O24]·H2O, previously determined at room temperature in the monoclinic space group C2/c from Weissenberg techniques [Don & Weakley (1981). Acta Cryst. B37, 451–453], has been redetermined from low-temperature single-crystal data in the monoclinic space group P21/c. The asymmetric unit contains one heptamolybdate anion, six guanidinium cations and one water molecule of hydration. The anions and cations are linked by an extensive network of N—H...O hydrogen bonds.