Synthesis, Structure and Properties of a Strontium（Ⅱ） Complex with 2, 3-Pyrazinedicarboxylic Acid

摘要

Complex [Sr2(pdc)2(H2O)7]·H2O (1, H2pdc = 2,3-pyrazinedicarboxylic acid) has been synthesized and characterized by single-crystal X-ray diffraction studies and FT-IR. Structural determination reveals that there are two crystallographically independent strontium ions in 1. The coordination geometry of Sr(1) is a nine-coordinated distorted monocapped tetragonal antiprism, while Sr(2) is a nine-coordinated distorted monocapped tetragonal prism. The ligand pdc2- takes two different connecting modes and links St(If) centers to generate a 2D layer structure. The 2D layers are linked through O-H...O and O-H...N hydrogen bonds to form a 3D framework structure. Thermal stability and luminescent properties of complex 1 are investigated. 1 belongs to the monoclinic system, space group P21 with a = 10.7182(10), b = 7.0377(6), c = 29.225(3) A, β = 95.7170(10)°, Z = 4, V = 2193.5(3) A3, Mr = 651.56, Dc = 1.973 g/cm3, F(000) = 1296,μ = 4.951 mm-1, the final R = 0.0318 and wR = 0.0726 for 3938 observed reflections with I 〉 2σ(/).