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Updated: Aug 8, 2026
08:53
Angle-resolved Photoemission Spectroscopy At Ultra-low Temperatures
Published on: October 9, 2012
Evidence for temperature-dependent electron band dispersion in pentacene
N Koch1, A Vollmer, I Salzmann
1Institut für Physik, Humboldt-Universität zu Berlin, Newtonstrasse 15, D-12489 Berlin, Germany. norbert.koch@physik.hu-berlin.de
Physical Review Letters
|May 23, 2006
Summary
Temperature affects electron band dispersion in pentacene thin films. This study used ultraviolet photoelectron spectroscopy to show that intermolecular electronic coupling in pentacene films depends on temperature and crystal structure.
Area of Science:
- Solid-state physics
- Materials science
- Organic electronics
Background:
- Pentacene thin films are promising organic semiconductors.
- Understanding their electronic properties is crucial for device applications.
- Electron band dispersion influences charge transport.
Purpose of the Study:
- To investigate temperature-dependent electron band dispersion in pentacene thin films.
- To explore the relationship between temperature, crystal structure, and intermolecular electronic coupling.
Main Methods:
- Angle- and energy-dependent ultraviolet photoelectron spectroscopy (ARPES).
- Infrared absorption spectroscopy.
Main Results:
- Evidence of temperature-dependent electron band dispersion in pentacene thin films on graphite.
- Highest occupied molecular orbital bands showed approximately 190 meV dispersion at room temperature and 240 meV at 120 K.
- Results suggest temperature and crystal structure influence intermolecular electronic coupling.
Conclusions:
- Intermolecular electronic coupling in pentacene thin films is temperature-dependent.
- Crystal structure may also play a role in this coupling.
- Findings contribute to understanding charge transport in organic semiconductors.
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