Rb(GaPO4)2(OH)(H2O).H2O: a hydrated rubidium gallium phosphate analogue of GaPO4.2H2O and leucophosphite.

Crystals of the title hydrated rubidium gallium phosphate, rubidium aqua-mu(3)-hydroxo-di-mu-phosphato-digallium hydrate, were synthesized hydrothermally at 453 K under autogenous pressure. The solid crystallizes in the monoclinic system and its structure was determined from single-crystal X-ray diffraction analysis. It is similar to dihydrated gallium phosphate, GaPO(4).2H(2)O, which is isostructural with the mineral leucophosphite. The structure is built up from a three-dimensional anionic framework composed of corner-linked octameric Ga(4)(PO(4))(4)(OH)(2)(H(2)O)(2) units. The Ga atom is in an octahedral coordination. Connection of the Ga(4)P(4) species generates eight-ring channels, in which are encapsulated the Rb(+) cations and water molecules.