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Title: Circular dichroism in photoelectron images from aligned nitric oxide molecules

Abstract

We have used velocity map photoelectron imaging to study circular dichroism of the photoelectron angular distributions (PADs) of nitric oxide following two-color resonanceenhanced two-photon ionization via selected rotational levels of the A 2Σ +, v' = 0 state. By using a circularly polarized pump beam and a counter-propagating, circularly polarized probe beam, cylindrical symmetry is preserved in the ionization process, and the images can be reconstructed using standard algorithms. The VMI set up enables individual ion rotational states to be resolved with excellent collection efficiency, rendering the measurements considerably simpler to perform than previous measurements conducted with a conventional photoelectron spectrometer. The results demonstrate that circular dichroism is observed even when cylindrical symmetry is maintained, and serve as a reminder that dichroism is a general feature of the multiphoton ionization of atoms and molecules. Furthermore, the observed PADs are in good agreement with calculations based on parameters extracted from previous experimental results obtained by using a time-offlight electron spectrometer.

Authors:
 [1];  [1]; ORCiD logo [2]
  1. Argonne National Lab. (ANL), Argonne, IL (United States)
  2. Univ. of Nottingham, Nottingham (United Kingdom)
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22), Chemical Sciences, Geosciences, and Biosciences Division; USDOE
OSTI Identifier:
1371761
Alternate Identifier(s):
OSTI ID: 1361854
Grant/Contract Number:
AC02-06CH11357
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Chemical Physics
Additional Journal Information:
Journal Volume: 147; Journal Issue: 1; Journal ID: ISSN 0021-9606
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS

Citation Formats

Sen, Ananya, Pratt, S. T., and Reid, K. L.. Circular dichroism in photoelectron images from aligned nitric oxide molecules. United States: N. p., 2017. Web. doi:10.1063/1.4982218.
Sen, Ananya, Pratt, S. T., & Reid, K. L.. Circular dichroism in photoelectron images from aligned nitric oxide molecules. United States. doi:10.1063/1.4982218.
Sen, Ananya, Pratt, S. T., and Reid, K. L.. Wed . "Circular dichroism in photoelectron images from aligned nitric oxide molecules". United States. doi:10.1063/1.4982218. https://www.osti.gov/servlets/purl/1371761.
@article{osti_1371761,
title = {Circular dichroism in photoelectron images from aligned nitric oxide molecules},
author = {Sen, Ananya and Pratt, S. T. and Reid, K. L.},
abstractNote = {We have used velocity map photoelectron imaging to study circular dichroism of the photoelectron angular distributions (PADs) of nitric oxide following two-color resonanceenhanced two-photon ionization via selected rotational levels of the A 2Σ+, v' = 0 state. By using a circularly polarized pump beam and a counter-propagating, circularly polarized probe beam, cylindrical symmetry is preserved in the ionization process, and the images can be reconstructed using standard algorithms. The VMI set up enables individual ion rotational states to be resolved with excellent collection efficiency, rendering the measurements considerably simpler to perform than previous measurements conducted with a conventional photoelectron spectrometer. The results demonstrate that circular dichroism is observed even when cylindrical symmetry is maintained, and serve as a reminder that dichroism is a general feature of the multiphoton ionization of atoms and molecules. Furthermore, the observed PADs are in good agreement with calculations based on parameters extracted from previous experimental results obtained by using a time-offlight electron spectrometer.},
doi = {10.1063/1.4982218},
journal = {Journal of Chemical Physics},
number = 1,
volume = 147,
place = {United States},
year = {Wed May 03 00:00:00 EDT 2017},
month = {Wed May 03 00:00:00 EDT 2017}
}

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  • We report a joint experimental and theoretical study of circular dichroism in the valence photoelectron spectra of a free chiral molecule. The circular dichroism in photoelectron spectroscopy is measured at the magic angle for various valence states of R(+) and S(-) methyl-oxirane enantiomers in the vapor phase. The maximum dichroism measured is about 5x10{sup -2}. Experimental and theoretical results are in agreement. The ab initio calculation employs a multicentric basis set of B-spline functions and a Kohn-Sham Hamiltonian.
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