The molecular structure of catena-[(mu-phthalato)-di-(mu-phthalazine)-di-silver(I)hydrate] ([Ag-2(mu-(O2C)(2)C6H4)(mu-PHZ)(2)(H2O)](n)): Carboxylate control of side-on versus stacked coordination polymerization

The crystal and molecular structure of catena-[(mu-phthalato)-di-(mu-phthalazine)-di-silver(I)hydrate], [Ag-2((O2C)(2)C6H4)(C8H6N2)(2)(H2O)], has been determined by single crystal X-ray analysis. The space group is tetragonal P4(3) with a=7.766(3), c=35.696(9) Angstrom, V=2152.9(13) Angstrom(3) and D-calc=2.031 g cm(-3) for Z=4. Phthalazine (PHZ) bridges the silver atoms to form [Ag-mu-PHZ](2) (2+) dimeric subunits. These dimeric subunits are planar (0.125 RMS) and are connected to each other by one of the phthalate carboxylates, which bridges the dimers to form a polymeric lattice. The other phthalate carboxylate is coordinated to a silver atom which is already coordinated by the first carboxylate, forming a seven-membered chelate ring. The second carboxylate is also hydrogen bonded to the water molecule in the structure's lattice. Consequently, the two silver atoms in the dimer are not the same. One atom is four-coordinate (two nitrogens and two oxygens) while the other silver atom is three-coordinate (two nitrogens but only one oxygen). The polymer structure results from side-on linking of the [Ag-mu-PHZ](2) (2+) dimeric subunits with the phthalate ligand, and is unlike the stacked polymer formed from the previously reported acetate linking of the same [Ag-mu-PHZ](2) (2+) dimeric subunits. The title complex is further characterized by its thermal properties, mass spectrum, C-13 solid state NMR and IR.