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

Abstract

Using a hydrothermal synthesis method, three novel silver complexes {Ag₂(H₂MDIP)(o-bix)₂·H₂O}_n(1) (H₄MDIP = methylenediisophthalic acid, o-bix = 1,2-bis (imidazol-1-ylmethyl)- benzene, {Ag₈(MDIP)₂(m-bix)}_n(2) (m-bix = 1,3-bis(imidazol-1-ylmethyl)-benzene), {Ag₄(MDIP)(p-bix)₃·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, π–π 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.