Syntheses, crystal structures, thermal stabilities and luminescence of two new zinc phosphonates.
Two new zinc phosphonates, [(C5H14N2)0.5Zn5(HO3PCH(OH)CO2)(O3PCH(OH)CO2)3 x 2 H2O] x 2 H2O (1) and [(C4H12N2)Zn2(O3PCH(OH)CO2)2] (2), have been synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction along with powder XRD, elemental analysis (EA), IR, and thermogravimetric analysis (TGA). In compound 1, [ZnO6] octahedra and [ZnO5] square-pyramids are bridged by 2-hydroxyl(phosphono)acetate with tri-, tetra-, and pentadentate coordination modes, resulting in a 3D framework possessing 1D 24-atom channels. In compound 2, 2-hydroxyl(phosphono)acetate exhibits a new tridentate coordination mode to link [ZnO4] tetrahedrons into a 2D hybrid layer. Both 2-methylpiperazine and piperazine serve as structure-directing agents, which are encapsulated into frameworks through electrostatic interactions and hydrogen bonding. Solids 1 and 2 display purple and yellow-green emission, respectively. It is interesting that solid 1 can give off bright white, yellow and orange-red emission under different heat-treatment temperatures. Furthermore, the luminescent color of solid 1-250 can be reversibly tuned among yellow-green, purple-blue, bright white and blue-green by shifting the wavelength of excited light.
State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Science, Fuzhou, Fujian 350002, China.
Ruibiao
R
Fu
Shengmin
S
Hu
Xintao
X
Wu