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Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Two new Dy3 triangles with trinuclear circular helicates and their single-molecule magnet behavior
Shuang-Yan Lin1, Lang Zhao, Yun-Nan Guo
1State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, People's Republic of China.
Inorganic Chemistry
|April 19, 2012
Summary
Two novel dysprosium(III) circular helicate complexes were synthesized. These structures exhibit unique magnetic properties, with one featuring the first reported μ(3)-azido-capped lanthanide complex, influencing relaxation dynamics.
Area of Science:
- Coordination Chemistry
- Supramolecular Chemistry
- Magnetochemistry
Background:
- Schiff base ligands are crucial in constructing complex coordination compounds.
- Lanthanide complexes are investigated for their unique magnetic properties.
- Circular helicates offer intricate structural architectures.
Purpose of the Study:
- To synthesize and characterize novel trinuclear triangular circular helicate dysprosium(III) complexes.
- To investigate the structural diversity influenced by reaction conditions (presence or absence of base).
- To explore the magnetic relaxation dynamics of the synthesized complexes.
Main Methods:
- Self-assembly synthesis utilizing a polydentate Schiff base ligand (H(3)L), dysprosium thiocyanate, and sodium azide.
- Single-crystal X-ray diffraction for detailed structural elucidation.
- AC susceptibility measurements to probe magnetic relaxation behavior.
Main Results:
- Two novel trinuclear triangular circular helicate dysprosium(III) complexes were successfully synthesized.
- Complex 1 features two μ(3)-methoxy oxygens capping the Dy(3) triangle.
- Complex 2 presents a μ(3)-azido- and μ(3)-hydroxyl-capped Dy(3) triangle, a first for lanthanide complexes.
- Complex 1 exhibits multiple relaxation processes, while Complex 2 shows slow magnetization relaxation.
- Distinct magnetic relaxation dynamics correlate with structural differences and Dy(III) coordination environments.
Conclusions:
- The synthetic strategy allows for control over the capping ligands of the Dy(3) triangle, leading to structural diversity.
- The μ(3)-azido ligand represents a novel capping motif in lanthanide chemistry.
- The observed magnetic relaxation phenomena are directly linked to the specific structural and electronic configurations of the dysprosium ions within the helicate framework.
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