Crystal structure of a silver(I) complex with the 1,2,4,5-benzenetetracarboxylic acid (pyromellitic acid)

The reaction between freshly precipitated silver oxide Ag2O and an aqueous solution of tetrabenzenecarboxylic acid H4L leads to the anhydrous Ag2H2L complex. It crystallizes in the space groupP21/c, witha=6.457(1),b=8.180(1),c=9.982(1) Å, β=97.83(1)°,V=522.3(1) Å3,Z=2,d=2.976 g cm−3. This structure is a three dimensional polymeric network polymer without any silver...silver interaction. The silver environment is a bipyramid trigonal polyhedron with three short bond distances in the equatorial plane (Ag−O=2.255(2), 2.295(2), and 2.499(2) Å) and two longer bond distances in axial positions (Ag−O=2.558(2) and 2.617(2) Å). Thus, the silver polyhedron involves five different ligands. It is noteworthy that the (H2L2)2− ligand is located around an inversion centre.