Synthesis, structure and near-infrared luminescence of a new 2D praseodymium(III) coordination polymer

A novel coordination polymer, [Pr2(BIPA)3(H2O)2]·2H2O (1) (H2BIPA=5-bromoisophthalic acid), was prepared by hydrothermal synthesis and characterized by IR spectroscopy, elemental analysis and single-crystal X-ray diffraction. The crystal was of monoclinic system, space group C2/c, with a=1.98037(14), b=1.44189(14), c=2.15281(18) nm, β=95.220(2)°, V=6.1218(9) nm3, C24H17Br3O16Pr2, Mr=1082.93, Dc= 2.350 g/cm3, F(000)=4096, μ=7.136 mm−1 and Z=8. The final R1=0.0608 and wR2=0.1371 for 5624 observed reflections (I>2σ(I)). Complex 1 featured an interesting 2D layer containing {Pr2(CO2)3}n right-handed and left-handed helical chains. Furthermore, hydrogen bonds linked the adjacent 2D layers to form a 3D supramolecular framework. Moreover, the near-infrared luminescent properties of 1 were also investigated in the solid state.