Solvothermal syntheses, structures and properties of two new In-MOFs based on rigid 1,4-naphthalenedicarboxylate ligand

Abstract

Two new indium MOFs based on rigid 1,4-naphthalenedicarboxylate (1,4-NDC) ligand have been successfully prepared under different solvothermal conditions and characterized by single crystal X-ray diffraction, powder X-ray diffraction, IR spectroscopy, TGA, elemental analyses and luminescence spectrum. In these two compounds, In(OH)(1,4-NDC)·2H2O (1) and HIn(1,4-NDC)2·2H2O·1.5DMF (2), (DMF=N, N′-dimethylformamide), 1,4-NDC exhibits two different coordination modes, constructing disparate architectures by bridging the different building units. Compound 1 exhibits a 3D framework with two kinds of square shape channels that built up from the infinite chains of corner-sharing In(OH)2O4 octahedra with 1,4-NDC ligands. Compound 2 possesses a 3D anion framework with twofold interpenetrating diamond topology which is accomplished by connecting four linear 1,4-NDC ligands to the four-connected In(III) nodes. Moreover, compounds 1 and 2 exhibit strong solid-state luminescence emissions at room temperature.