Solvothermal synthesis, crystal structure, and second-order nonlinear optical properties of a new noncentrosymmetric gallium-organic framework material, [N(C3H7)(4)](3)Ga-3[C6H3(CO2)(3)](4)

Abstract

A novel noncentrosymmetric (NCS) gallium-organic framework material, [N(C3H7)(4)](3)Ga-3[C6H3(CO2)(3)](4) (CAUMOF-11) has been synthesized by a solvothermal reaction using Ga(NO3)(3)center dot xH(2)O, 1,3,5-C6H3(CO2H)(3), N(C3H7)(4)Cl, HNO3, and HCON(CH3)(2) at 180 degrees C. The structure of the reported material has been determined by single-crystal X-ray diffraction. CAUMOF-11 has an anionic three-dimensional framework with aligned four-coordinate GaO4 tetrahedra and 1,3,5-benzenetricarboxylate groups. Tetrapropylammonim cations reside within the channel and maintain the charge balance. Detailed structural analyses with full characterization including infrared spectroscopy, thermogravimetric analysis, elemental analysis, ion-exchange reactions, topotactic decomposition, and gas adsorption experiments are reported. Powder second-harmonic generating (SHG) measurements on CAUMOF-11, using 1064 nm radiation, exhibit SHG efficiency of 15 times that of alpha-SiO2 and the material is phase-matchable (type-1). (C) 2012 Elsevier Inc. All rights reserved.