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Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
Published on: February 7, 2022
Structural dynamics of photoinduced molecular switching in the solid state
Hervé Cailleau1, Maciej Lorenc, Laurent Guérin
1Institut de Physique de Rennes, Université de Rennes1-CNRS, UMR 6251, F-35042 Rennes, France. herve.cailleau@univ-rennes1.fr
Acta Crystallographica. Section A, Foundations of Crystallography
|February 19, 2010
Summary
Ultra-fast X-ray diffraction reveals complex structural dynamics in photoswitchable materials. This study tracks molecular switching, volume expansion, and thermoswitching across different timescales, crucial for material design.
Area of Science:
- Materials Science
- Solid-State Physics
- Physical Chemistry
Background:
- Ultra-fast time-resolved diffraction enables direct observation of material structural dynamics.
- Understanding material rearrangement during laser-induced transformations is key for controlling macroscopic photoswitching.
- Molecular bistability in spin-crossover materials serves as a model for solid-state molecular switching.
Purpose of the Study:
- To investigate the structural dynamics of photoinduced molecular switching in the solid state.
- To elucidate the complex pathway and timescale-dependent nature of material transformations.
- To explore the dynamics in multifunctional spin-crossover materials.
Main Methods:
- Utilizing 100 picosecond (ps) X-ray diffraction to probe structural changes.
- Employing ultra-short laser pulses to induce photoexcitation and subsequent material rearrangement.
- Analyzing dynamics across molecular, nanosecond, and microsecond timescales.
Main Results:
- Observed subpicosecond molecular photoswitching initiated by laser pulses.
- Detected volume expansion occurring on a nanosecond timescale.
- Identified additional thermoswitching phenomena on a microsecond timescale.
Conclusions:
- Material transformations involve complex pathways spanning multiple timescales.
- The nature of dynamical processes and involved degrees of freedom are timescale-dependent.
- Time-resolved X-ray diffraction is essential for understanding and directing photoswitching in advanced materials.
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