학술논문
Self-assembly of Schiff base anions and the trapping of HO− , O2− and Piv− bridges in a family of Ni3 Ln4 complexes: synthesis, structures and magnetic properties.
Document Type
Article
Source
Subject
*MAGNETIC structure
*SCHIFF bases
*MAGNETIC properties
*ANIONS
*X-ray diffraction
*BENZOIC acid
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Language
ISSN
1144-0546
Abstract
A unique family of heptanuclear 3d–4f complexes, [Ni3Ln4L3(OH)3O(Piv)6(MeOH)2(OMe)]·nH2O (Ln = Dy (1), Tb (2), Ho (3); Piv = Me3CCO2−), has been synthesized using a Schiff-base H2L (L = 2-((2-hydroxy-3-methoxybenzylidene)amino)benzoic acid), NEt3, NiCl2·6H2O and Ln(NO3)3·5H2O in a refluxing MeOH–CHCl3 solvent mixture. Single-crystal X-ray diffraction studies revealed that the coordination aggregates were grown around a unique μ4-O2− unit, which connects four lanthanide ions. Three supporting μ3-HO− ions were used to connect three L2−-bound Ni⋯Ln fragments to the central LnIII center, which is not coordinated to any Schiff-base anion. Six μ1,3-pivalate anions extended further support for the three L2−-bound Ni⋯Ln fragments and three Ln⋯Ln fragments. Magnetic studies of 1–3 in the solid state are consistent with weak antiferromagnetic interactions between the 3d and 4f ions. [ABSTRACT FROM AUTHOR]