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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Temperature-directed structural recurrence in low-symmetric Co(II) complexes and nanocrystals
Yan-Yan Yin1, Xiao-Yan Chen, Xiao-Chang Cao
1Department of Chemistry and Key Laboratory of Advanced Energy Materials Chemistry (MOE), Nankai University, Tianjin 300071, China.
Chemical Communications (Cambridge, England)
|December 3, 2011
Summary
New cobalt complexes and their nanocrystals show repeating structural behavior. These materials exhibit dynamic changes in chiral, nonlinear optical, and ferroelectric properties with temperature variations.
Area of Science:
- Coordination Chemistry
- Materials Science
- Crystallography
Background:
- Low-symmetric metal-organic complexes can exhibit unique physical properties.
- Nanocrystals of coordination compounds offer enhanced surface area and tunable characteristics.
- Structural recurrence and property changes in materials are key areas of research.
Purpose of the Study:
- To synthesize and characterize novel low-symmetric cobalt complexes and their corresponding nanocrystals.
- To investigate the structural recurrence behavior of these materials at various temperatures.
- To explore the temperature-dependent changes in chiral, nonlinear optical (NLO), and ferroelectric properties.
Main Methods:
- Solvothermal synthesis of cobalt complexes.
- Crystallization to obtain bulk and nano-scale materials.
- Variable-temperature X-ray diffraction (XRD) for structural analysis.
- Chirality measurements, nonlinear optical (NLO) measurements, and ferroelectric property testing.
Main Results:
- Two low-symmetric cobalt complexes, {[Co(μ(2)-L)(H(2)O)(2)]·H(2)O}(n) (1) and {[Co(μ(3)-L)(H(2)O)]·0.5H(2)O}(n) (2), and their nanocrystals were successfully obtained.
- Observed structural recurrence behavior in the complexes across different temperature ranges.
- Demonstrated significant changes in chiral, nonlinear optical, and ferroelectric properties correlated with temperature-induced structural transitions.
Conclusions:
- The synthesized cobalt complexes and nanocrystals display temperature-dependent structural dynamics.
- These materials exhibit tunable chiral, nonlinear optical, and ferroelectric properties, making them promising for advanced applications.
- The study highlights the potential of low-symmetric coordination compounds in responsive materials design.
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