The synthesis and characterization of a novel three-dimensional gallium phosphatooxalate is described; the structure consists of GaO4 tetrahedra and GaO6 octahedra linked by phosphate and oxalate groups to form two-dimensional sheets between which are GaO4N square pyramids, generating tunnels in which the monoprotonated 4,4'-bipyridine molecules reside; Ga-71 MAS NMR confirms the presence of four-, five- and six-coordinate Ga atoms.
