No Cover Image

Journal article 329 views

Accurate depolarization ratio measurements for all diatomic hydrogen isotopologues

T. M James, M Schlösser, S Fischer, M Sturm, B Bornschein, R. J Lewis, H. H Telle, Helmut Telle, Timothy James

Journal of Raman Spectroscopy, Volume: 44, Issue: 6, Pages: 857 - 865

Swansea University Authors: Helmut Telle, Timothy James

Full text not available from this repository: check for access using links below.

Check full text

DOI (Published version): 10.1002/jrs.4283

Abstract

The Raman depolarization ratios for individual Q1(J”) branch lines of all diatomic hydrogen isotopologues – H2, HD, D2, HT, DT, and T2 – were measured, for all rotational levels with population larger than 1/100 relative to the Boltzmann maximum at room temperature. For these measurements, the exper...

Full description

Published in: Journal of Raman Spectroscopy
ISSN: 0377-0486
Published: 2013
Online Access: Check full text

URI: https://cronfa.swan.ac.uk/Record/cronfa14493
Tags: Add Tag
No Tags, Be the first to tag this record!
Abstract: The Raman depolarization ratios for individual Q1(J”) branch lines of all diatomic hydrogen isotopologues – H2, HD, D2, HT, DT, and T2 – were measured, for all rotational levels with population larger than 1/100 relative to the Boltzmann maximum at room temperature. For these measurements, the experimental setup normally used for the monitoring of the tritiated hydrogen molecules at the KArlsruhe TRItium Neutrino experiment was adapted to optimally control the excitation laser power and polarization, and to precisely define the Raman light collection geometry. The measured Raman depolarization values were compared to theoretical values, which are linked to polarizability tensor quantities. For this, the ‘raw data’ were corrected taking into account distinct aspects affecting Raman depolarization data, including (1) excitation polarization impurities; (2) extended Raman excitation volumes; and (3) Raman light collection over finite solid angles. Our corrected depolarization ratios of the hydrogen isotopologues agree with the theoretical values (based on ab initio quantum calculations by R.J. LeRoy, University of Waterloo, Canada) to better than 5% for nearly all of the measured Q1(J”) lines, with 1-sigma confidence level. The results demonstrate that reliable, accurate Raman depolarization ratios can be extracted from experimental measurements, which may be substantially distorted by excitation polarization impurities and by geometrical effects.
College: Faculty of Science and Engineering
Issue: 6
Start Page: 857
End Page: 865