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Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Reversible structural transition in MIL-53 with large temperature hysteresis.
Yun Liu1, Jae-Hyuk Her, Anne Dailly
1NIST Center for Neutron Research, 100 Bureau Drive, Gaithersburg, Maryland, USA. yunliu@nist.gov.
Journal of the American Chemical Society
|August 13, 2008
Summary
Metal-organic frameworks (MOFs) like MIL-53 show a reversible "breathing" structural transition. This study reveals this transition occurs with temperature changes, even without guest molecules, and exhibits significant thermal hysteresis.
Area of Science:
- Materials Science
- Chemistry
- Physics
Background:
- Metal-organic frameworks (MOFs) exhibit structural flexibility, often triggered by guest molecule adsorption, leading to a phenomenon known as
Purpose of the Study:
- Investigate the temperature-induced structural transitions in MIL-53 MOFs.
- Determine if guest molecules are essential for the
Main Methods:
- Neutron powder diffraction
- Inelastic neutron scattering
- Ab initio computer simulations
Main Results:
- MIL-53 undergoes a reversible structural transition between open-pored and closed-pored states solely based on temperature.
- A significant thermal hysteresis was observed: open-to-closed transition at 125-150 K and closed-to-open transition at 325-375 K.
- The transition from open to closed structure at low temperatures exhibits slow kinetics.
Conclusions:
- Guest molecules are not required for the
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