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Updated: Oct 7, 2025
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High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
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Temperature-Dependent Structural Phase Transition in Rubrene Single Crystals: The Missing Piece from the Charge
Arie van der Lee1, Maurizio Polentarutti2, Gilles H Roche3,4
1IEM, Université de Montpellier, CNRS, ENSCM, 34095 Montpellier, France.
The Journal of Physical Chemistry Letters
|January 5, 2022
Summary
Structural models reveal that rubrene’s tetracene units slip below 200 K, coinciding with a hole mobility crossover. This slip is linked to thermal expansion and angle changes, impacting electronic couplings in organic semiconductors.
Area of Science:
- Materials Science
- Solid-State Physics
- Organic Electronics
Background:
- Rubrene is a benchmark organic semiconductor crucial for electronic applications.
- Understanding molecular packing and its temperature dependence is key to optimizing charge transport.
Purpose of the Study:
- To investigate the structural dynamics of rubrene crystals.
- To correlate molecular motion with charge transport properties.
Main Methods:
- Synchrotron X-ray diffraction was used to obtain accurate structural models.
- Temperature-dependent studies were conducted in the range of 100-300 K.
- Density Functional Theory (DFT) calculations were employed to analyze electronic couplings.
Main Results:
- Rubrene’s cofacial tetracene units are blocked until 200 K, then slip.
- The slip temperature correlates with the observed hole mobility crossover.
- Structural blocking is attributed to negative correlations between thermal expansion and inter-unit angles.
Conclusions:
- Molecular slippage is a critical factor influencing charge transport in rubrene.
- Temperature-dependent structural changes directly impact electronic couplings and semiconductor performance.
- These findings provide insights for designing high-performance organic electronic materials.
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