Keywords: two-dimensional coordination polymer; zinc(II); 5,5 0 -methylenebis(2,4,6-trimethylisophthalic acid; 2,7-bis(1H-imidazol-1yl)fluorene; hydrogen bonding; fluorescence properties; crystal structure; supramolecular. CCDC reference: 1875032Supporting information: this article has supporting information at journals.iucr.org/c A three-dimensional Zn II coordination network based on 5,5 0 0 0 -methylenebis(2,4,6-trimethylisophthalic acid) and 2,7-bis(1H-imidazol-1-yl)fluorene: synthesis, structure and luminescence properties In recent years, coordination polymers constructed from multidentate carboxylate ligands and N-containing ligands have attracted much attention since these ligands can adopt a rich variety of coordination modes which can lead to crystalline products with intriguing structures and interesting properties. A new coordination polymer, namely poly[[diaqua [-2,7-.5H 2 O} n , 1, was prepared by the self-assembly of Zn(NO 3 ) 2 Á6H 2 O with 5,5 0 -methylenebis(2,4,6trimethylisophthalic acid) (H 4 BTMIPA) and 2,7-bis(1H-imidazol-1-yl)fluorene (BIF) under solvothermal conditions. The structure of 1 was determined by elemental analysis, single-crystal X-ray crystallography, powder X-ray diffraction, IR spectroscopy and thermogravimetric analysis. Each Zn II ion is sixcoordinated by two O atoms from two H 2 BTMIPA 2À ligands, by two N atoms from two BIF ligands and by two water molecules, forming a distorted octahedral ZnN 2 O 4 coordination geometry. Adjacent Zn II ions are linked by H 2 BTMIPA 2À ligands and BIF ligands, leading to the formation of a twodimensional (2D) (4,4)-sql network, and intermolecular hydrogen-bonding interactions connect the 2D layer structure into the three-dimensional (3D) supramolecular structure. Each 2D layer contains two kinds of helices with the same direction, which are opposite in adjacent layers. The luminescence properties of complex 1 in the solid state have also been investigated.