鑭（Ⅲ）金屬在含吡啶-3,5-雙羧酸根自我組裝三維配位結構：合成及結構

Self-assembly of 3-D Lanthanum(Ⅲ) coordination frameworks based on pyridine-3,5-dicarboxylate: synthesis and structure

沈福銘(Fwu-Ming Shen) ； 駱詩富(Shie-Fu Lush)

《元培學報》 23期 (2017/12) Pp. 47-56

摘要

高分子聚合物[La_2（C_7H_3NO_4）_3(H_2O)_3]_n，包含兩個獨立La（Ⅲ）離子，三個吡啶-3,5-雙羧酸根陰離子及配位三個水分子，兩個La（Ⅲ）離子使用吡啶雙羧酸根陰離子當橋鍵形成雙核單元體。每個吡啶-3,5-雙羧酸根陰離子顯示四種連結模式。La1 離子連接九個氧原子分別來自六個吡啶-3,5-雙羧酸根陰離子及兩個水分子，形成九配位四面平方帽四方稜柱形的幾何結構。另一個La2離子連接七個氧原子分別來自六個吡啶-3,5-雙羧酸根陰離子及一個水分子，形成七配位4,4'-雙帽三角錐形的幾何結構。結構中含有典型氫鍵（O-H．．．O、O-H．．．N）作用力及非典型的分子（內）間氫鍵作用（C-H．．．O），以及吡啶環之間的π-π吸引力，[其中心最近距離為3.7749（15）Å，兩芳香環的雙面角為5.78 (12)°]

關鍵字

水熱合成 ； 吡啶-3,5-雙羧酸 ； 鑭（Ⅲ）-錯合物 ； 氫鍵

並列摘要

The polymer compound, [La_2(C_7H_3NO_4)_3(H_2O)_3]_n, contains two independent La^(Ⅲ) ions, three pyridine-3,5-dicarboxylate anions and three coordinated water molecules in which two La^(Ⅲ) ions are bridged by carboxylate and forms dinuclear unit. Each pyridine-3,5-dicarboxylate anion affords a four-connecting nodes. Around nine-coordinated La^(Ⅲ) cation (La1) is completed by nine oxygen atoms from six pyridine-3,5-dicarboxylate and two aqua, forming a square-face capped square antiprism. Other seven-coordinated La^(Ⅲ) cation (La2) is coordinated with seven oxygen atoms from six pyridine-3,5-dicarboxylate and one aqua, forming a 4,4'-bicapped trigonal prism. There are classical hydrogen bondings (O-H．．．O and O-H．．．N) and weak non-classical hydrogen bondings (C-H．．．O) is observed in the crystal structure. The crystal structure is further consolidated by π．．．π stacking between nearly parallel pyridine rings of adjacent pyridine-3,5- dicarboxylate ligands [shortest centroid-centroid distance between π．．．π is 3.7749 (15)Å, dihedral angle = 5.78 (12)°].

並列關鍵字

Hydrothermal synthesis ； Pyridine-3,5-dicarboxylate ； Lanthanum(Ⅲ) Complexes ； Hydrogen bonding