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Updated: Jul 6, 2026

Spatial Separation of Molecular Conformers and Clusters

Spatial Separation of Molecular Conformers and Clusters

Published on: January 9, 2014

Inelastic electron interaction with chloroform clusters embedded in helium droplets.

Stephan Denifl¹, Fabio Zappa, Ingo Mähr

¹Institut für Ionenphysik and Angewandte Physik and Center for Molecular Biosciences Innsbruck, Leopold-Franzens Universität Innsbruck, Technikerstrasse 25, A-6020 Innsbruck, Austria.

Journal of the American Chemical Society

|March 14, 2008

Summary

Inelastic electron interactions with chloroform in helium droplets reveal cluster formation and stabilize transient negative ions, unlike in the gas phase.

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Area of Science:

Physical Chemistry
Atomic and Molecular Physics
Chemical Physics

Background:

Electron-molecule interactions are fundamental to chemistry and physics.
Understanding ionization and attachment processes is crucial for various applications.
Helium droplets offer a unique environment for studying molecular interactions.

Purpose of the Study:

To investigate inelastic electron scattering (ionization/attachment) with chloroform.
To explore the formation of chloroform clusters in helium droplets.
To analyze the stabilization of transient negative ions in a cluster environment.

Main Methods:

Utilized a two-sector field mass spectrometer.
Studied electron ionization and attachment at specific electron energies (70 eV and 1.5 eV).
Analyzed positive and negative ion mass spectra of chloroform embedded in helium droplets.

Main Results:

Chloroform clusters readily form within helium droplets.
Transient negative ions of chloroform, unobservable in the gas phase, are stabilized.
Ion yield of anions was determined as a function of electron energy.

Conclusions:

Helium droplet environment significantly influences electron interaction processes with chloroform.
Cluster formation aids in the stabilization of otherwise short-lived molecular anions.
This study provides insights into electron-molecule interactions in a condensed phase-like environment.