Hydrothermal synthesis, structure, and properties of lead(II)-based coordination compounds with R-isophthalic acid (R = OH, CH3)

Three new lead(II)-based coordination polymers, [Pb(5-OH-BDC)](n)center dot nH(2)O (1) (5-OH-BDC = 5-hydroxyisophthalate), [Pb-2(5-CH3-BDC)(2)](n) (2), and [Pb-2(5-CH3-BDC)(2)(phen)(2)](n)center dot 2nH(2)O (3) (5-CH3-BDC = 5-methylisophthalate, phen = 1,10-phenanthroline), have been hydrothermally synthesized, structurally determined by single-crystal X-ray diffraction, and characterized by elemental analyses, IR spectra, and thermogravimetric analyses. Both 1 and 2 exhibit 2-D double-layer network structures, while 3 possesses 1-D chain structure bridged by 5-CH3-BDC. The coordination sphere of Pb(II) in 1 is holodirected, whereas in 2 and 3 the spheres feature hemidirected structures. Fluorescence properties of 1-3 have been investigated in the crystalline state at room temperature.