关键词: 3 ,5-吡啶二甲酸;2 ,4 ,6-吡啶三甲酸;铕;配位聚合物;晶体结构;光致发光

Abstract: A 3D europium coordination polymer {[Eu2(2,4,6-Hptc)( 3,5-pdc)2(H2O)8]·6H2O}n(1) (2, 4, 6-H3 ptc = 2, 4, 6-pyridinetricarboxylic acid;3, 5-H2 pdc = 3, 5-pyridinedicarboxylic acid ) was synthesized by hydrothermal method using europium perchlorate reacting with 3,5-pyridinedicarboxylic acid and 2,4,6-pyridinetricarboxylic acid. X-ray diffraction analysis of single crystal shows that the complex is crystallized in monoclinic system, C2/c space group. The cell parameters are as follows a=2. 0106(11) nm,b=1. 1048(6) nm,c=1. 7591(10) nm,β = 112. 117(8) °,α = γ = 90°. Eu3+ ions in the complex is coordinated with nine oxygen atoms. Five O atmos are from the carboxylate of lignds and the other four O atoms are from coordination water molecules. They are formed a distorted tricapped trigonal prism. The two carboxylates of each 3,5-pdc anion coordinates with Eu3+ by chelating way and a 1D chain structure is formed. 2,4,6-Hptc anions coordinate with Eu3+ by the 2-and 4-carboxylates. The 4-carboxylate does not coordinate. The 1D chain structres formed with 3,5-pdc anions and Eu3+ are further connected by 2,4,6-Hptc anions and 1D ladder shaped structure are constructed. The complex exhibits intense characteristic luminescence of Eu3+ with excitation of UV-rays.

Key words: A 3D europium coordination polymer {[Eu2(2,4,6-Hptc)( 3,5-pdc)2(H2O)8]·6H2O}n(1) (2, 4, 6-H3 ptc = 2, 4, 6-pyridinetricarboxylic acid;3, 5-H2 pdc = 3, 5-pyridinedicarboxylic acid ) was synthesized by hydrothermal method using europium perchlorate reacting with 3,5-pyridinedicarboxylic acid and 2,4,6-pyridinetricarboxylic acid. X-ray diffraction analysis of single crystal shows that the complex is crystallized in monoclinic system, C2/c space group. The cell parameters are as follows a=2. 0106(11) nm,b=1. 1048(6) nm,c=1. 7591(10) nm,β = 112. 117(8) °,α = γ = 90°. Eu3+ ions in the complex is coordinated with nine oxygen atoms. Five O atmos are from the carboxylate of lignds and the other four O atoms are from coordination water molecules. They are formed a distorted tricapped trigonal prism. The two carboxylates of each 3,5-pdc anion coordinates with Eu3+ by chelating way and a 1D chain structure is formed. 2,4,6-Hptc anions coordinate with Eu3+ by the 2-and 4-carboxylates. The 4-carboxylate does not coordinate. The 1D chain structres formed with 3,5-pdc anions and Eu3+ are further connected by 2,4,6-Hptc anions and 1D ladder shaped structure are constructed. The complex exhibits intense characteristic luminescence of Eu3+ with excitation of UV-rays.