A novel 2D coordination polymer with unprecedented [Ag]7 chains and two 3D silver-organic frameworks constructed by methylenediisophthalic acid (H4MDIP) with strong Ag-Ag interactions

Using a hydrothermal synthesis method, three novel silver complexes {Ag-2(H2MDIP)(o-bix)(2)center dot H2O}(n)(1) (H4MDIP = methylenediisophthalic acid, o-bix = 1,2-bis (imidazol-1-ylmethyl)-benzene, {Ag-8(MDIP)(2)(m-bix)}(n)(2) (m-bix = 1,3-bis(imidazol-1-ylmethyl)-benzene), {Ag-4(MDIP)(p-bix)(3)center dot H2O}(n)(3) (p-bix = 1,4-bis(imidazol-1-ylmethyl)-benzene) were synthesized based on tetracarboxylic acid and auxiliary ligands containing N donors. Their structures have been characterized by X-ray crystallography. Complexes 1 and 3 have special 3D supramolecular networks constructed by hydrogen bonding, pi-pi stacking and electronic interactions to link the metal cations, anions and water molecules together. Complex 2 exhibits a unique 2D architecture with unprecedented [Ag](7) chains connected by strong Ag-Ag interactions. Thermal stabilities and luminescent properties of complexes 1-3 were investigated.