The First Vanadium Gallophosphates: Hydrothermal Synthesis and Structure of Rb [(VO)(H2O)Ga(PO4)2] and Cs [(VO)(H2O)Ga(PO4)2]

The first examples of vanadium gallophosphates, Rb[(VO)(H2O)Ga(PO4)2] and Cs[(VO)(H2O)Ga(PO4)2] have been synthesized using hydrothermal methods, fromXVO3(X=Rb, Cs), Ga2O3, H3PO4, H2PO3F, and an organic species. The phases are isostructural and have a three-dimensional anionic vanadium gallophosphate framework assembled from corner sharing PO4and GaO4tetrahedra and VO5(H2O) octahedra. The PO4and GaO4tetrahedra form chains which are crosslinked by the vanadium octahedra. Since the GaO4tetrahedra and VO5(H2O) octahedra each share corners exclusively with PO4tetrahedra, no Ga–O–V bonding is present in the framework. The anionic charge of the framework is compensated by the alkali cations, which lie in tunnels running along theyaxis. Single-crystal data for Rb[(VO)(H2O)Ga(PO4)2]: monoclinic, space groupP21/c(No. 14) witha=7.928(2) ?,b=8.049(2) ?,c=13.983(3) ?,BETA=104.274(5)°,V=864.8(4) ?3,Z= 4,Dcalc=3.303 g cm-3; for Cs[(VO)(H2O)Ga(PO4)2]: monoclinic, space groupP21/c(No. 14) witha=8.0423(5) ?,b= 8.0661 (5) ?,c=14.1284(8) ?,BETA=105.094(1)°,V=884.89(9) ?3,Z=4,Dcalc=3.584 g/cm-3.