Hydrothermal Syntheses, Crystal Structures, Magnetism and Fluorescence Quenching of Oxamidato-Bridged Pentanuclear CuII4LnIII Complexes Containing Macrocyclic Ligands (Ln = Eu, Tb) and the Crystal Structure of a Hexanuclear NiII5SmIII Complex
✍ Scribed by Ya-Qiu Sun; Mao Liang; Wen Dong; Guang-Ming Yang; Dai-Zheng Liao; Zong-Hui Jiang; Shi-Ping Yan; Peng Cheng
- Publisher
- John Wiley and Sons
- Year
- 2004
- Tongue
- English
- Weight
- 184 KB
- Volume
- 2004
- Category
- Article
- ISSN
- 1434-1948
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✦ Synopsis
Abstract
Three novel oxamidato‐bridged complexes incorporating a macrocyclic oxamide of formula (CuL)~3~{CuL(C~2~H~5~OH)}Eu(H~2~O)~3~·1.5H~2~O (1), (CuL)~3~{CuL(C~2~H~5~OH)}Tb(H~2~O)~3~·2H~2~O (2) and (NiL)~5~Sm~3~·2H~2~O (3) (CuL and NiL, H~2~L = 2,3‐dioxo‐5,6,14,15‐dibenzo‐1,4,8,12‐tetraazacyclopentadeca‐7,13‐dien), have been hydrothermally synthesized and structurally characterized. In these complexes, the central Ln^III^ and external copper (or nickel) ions are bridged by macrocyclic oxamide groups. The Eu^III^ (or Tb^III^) ion of 1 (or 2) resides in a distorted tricapped trigonal prismatic environment surrounded by eight oxygen atoms from four oxamide groups and one oxygen atom from a water molecule, whereas the Sm^III^ ion of 3 resides in a distorted bicapped square antiprismatic environment surrounded by ten oxygen atoms from five oxamide groups. Furthermore, there are hydrogen bonding interactions in 1 and 2 between perchlorate, ethanol and water moieties. Especially for 1 and 2, O−H···O and weak coordination of ClO~4~^−^ groups link the pentanuclear fragments and perchlorate ions to form a 1‐D supramolecular architecture. The fluorescence of Eu^III^ and Tb^III^ are almost completely quenched in 1 and 2. The magnetic properties of 1 and 2 have been characterized. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)