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Electron attenuation in free, neutral ethane clusters
M Winkler1, V Myrseth2, J Harnes1
1Department of Chemistry, University of Bergen, NO-5007 Bergen, Norway.
The Journal of Chemical Physics
|November 3, 2014
Summary
The electron effective attenuation length (EAL) in ethane clusters was measured using X-ray photoelectron spectroscopy. The study determined the EAL to be 8.4 ± 1.9 Å, consistent with theoretical predictions.
Area of Science:
- Physical Chemistry
- Surface Science
- Spectroscopy
Background:
- The electron effective attenuation length (EAL) is crucial for understanding electron transport in materials.
- Previous studies have estimated EAL using indirect methods, lacking direct experimental validation in specific cluster environments.
Purpose of the Study:
- To experimentally determine the electron effective attenuation length (EAL) in free, neutral ethane clusters.
- To validate theoretical models for electron transport in molecular clusters.
Main Methods:
- Utilized carbon 1s X-ray photoelectron spectroscopy (XPS) at 40 eV kinetic energy.
- Employed theoretical lineshape modeling to determine cluster size (N) and EAL (λ) by optimizing spectral fits.
- Produced ethane clusters via adiabatic expansion with helium, with mean sizes ranging from 100-600 molecules.
Main Results:
- The electron effective attenuation length (EAL) in ethane clusters was determined to be 8.4 ± 1.9 Å.
- This experimental value shows good agreement with an independent estimate of 10 Å derived from electron-scattering data and Monte Carlo simulations.
Conclusions:
- The study provides a direct experimental measurement of EAL in ethane clusters.
- The findings support the reliability of theoretical modeling for predicting electron transport properties in such systems.
- The influence of cluster aggregation state and temperature on EAL was discussed.
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