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Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Structural phase transition of Gd3RuO7.
Nobuo Ishizawa1, Kenji Tateishi, Saki Kondo
1Ceramics Research Laboratory, Nagoya Institute of Technology, Tajimi, Gifu, Japan 507-0071. ishizawa@nitech.ac.jp
Inorganic Chemistry
|December 19, 2007
Summary
Trigadorinium ruthenium heptaoxide (Gd(3)RuO(7)) undergoes a reversible structural phase transition. This transition involves octahedral tilts and a change in Gd atom coordination, revealing previously unreported structural disorder.
Area of Science:
- Solid-state chemistry
- Crystallography
- Materials science
Background:
- Lanthanide ruthenates (Ln(3)RuO(7)) and osmates (Ln(3)OsO(7)) exhibit archetypal Cmcm structures.
- Understanding structural phase transitions is crucial for materials design.
Purpose of the Study:
- To investigate the structural phase transition of gadolinium ruthenium heptaoxide (Gd(3)RuO(7)).
- To characterize the structural changes associated with the transition using high-temperature single-crystal X-ray diffraction.
Main Methods:
- In situ high-temperature single-crystal X-ray diffraction.
- Structure determination of both high-temperature (Cmcm) and low-temperature (P2(1)nb) phases.
- Analysis of unit cell parameters and atomic coordination.
Main Results:
- A reversible structural phase transition was observed between 363 and 383 K.
- The transition involves tilts of RuO(6) octahedra and a reduction in Gd atom coordination number.
- Structural disorder involving Gd atom distribution was identified in the high-temperature Cmcm phase.
Conclusions:
- The structural phase transition in Gd(3)RuO(7) is characterized by octahedral tilts and coupled changes in Gd coordination.
- The study reveals novel structural disorder in the high-temperature phase, differing from archetypal Ln(3)RuO(7) and Ln(3)OsO(7) structures.
- This finding contributes to a deeper understanding of phase transitions and structural complexity in rare-earth metal oxides.
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