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Updated: Jun 1, 2026

Direct Imaging of Laser-driven Ultrafast Molecular Rotation
Published on: February 4, 2017
Experimental observation of rotational Doppler broadening in a molecular system
1Department of Chemistry, Oregon State University, Corvallis, Oregon 97331, USA.
Abstract:
The first experimental evidence of rotational Doppler broadening in photoelectron spectra, reported here, show good agreement with recently described theoretical predictions. The dependence of the broadening on temperature and photoelectron kinetic energy is quantitatively predicted by the theory. The experiments verify that the rotational contributions to the linewidth are comparable to those from translational Doppler broadening and must be considered in the analysis of high-resolution photoelectron spectra. A classical model accounting for this newly observed effect is presented.
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