Hydrothermal synthesis and crystal structure of the microporous gallophosphate [NH₄]₄[Ga₈P₈O₃₂(OH)₄(H₂O)₄]·4H₂O·0.64PrOH with an octahedral–tetrahedral framework

Abstract

The new microporous gallophosphate, [NH4]4[Ga8P8O32(OH)4(H2O)4]·4H2O·0.64PrOH, has been synthesised and structurally characterised; it has a framework isostructural with that of [NH4][Al2(OH)(HPO4)2]·2H2O. The gallophosphate consists of gallium-centred octahedra (GaO6) and phosphorus-centred tetrahedra (PO4) which together serve as basic building units to form a three-dimensional framework structure. The gallophosphate crystallises in monoclinic symmetry with space group P21/n, a= 9.6814(0), b= 9.6568(0), c= 9.7618(0)Å and β= 102.90(5)°. The structure possesses three-dimensional channels with eight-ring windows running along the [100], [010] and [001] axes in which organic template molecules and inorganic NH+4 cations in pairs are located.