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Title: Absorption spectroscopy of the rubidium dimer in an overheated vapor: An accurate check of molecular structure and dynamics

Abstract

Experimental studies of the absorption spectrum of the Rb{sub 2} dimer are performed in the 600-1100 nm wavelength range for temperatures between 615 and 745 K. The reduced absorption coefficient is measured by spatially resolved white light absorption in overheated rubidium vapor with a radial temperature gradient, which enables simultaneous measurements at different temperatures. Semiclassical and quantum spectral simulations are obtained by taking into account all possible transitions involving the potential curves stemming from the 5 {sup 2}S+5 {sup 2}S and 5 {sup 2}S+5 {sup 2}P asymptotes. The most accurate experimental potential curves are used where available, and newly calculated potential curves and transition dipole moments otherwise. The overall consistency of the theoretical model with the experimental interpretation is obtained only if the radial dependence of both the calculated transition dipole moments and the spin-orbit coupling is taken into account. This highlights the low-resolution absorption spectroscopy as a valuable tool for checking the accuracy of molecular electronic structure calculations.

Authors:
; ; ;  [1]; ;  [2]
  1. Institute of Physics, Bijenicka 46, 10000 Zagreb (Croatia)
  2. Laboratoire Aime Cotton, CNRS, Campus d'Orsay, 91405 Orsay Cedex (France)
Publication Date:
OSTI Identifier:
20982309
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevA.75.032512; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; ABSORPTION; ABSORPTION SPECTRA; ABSORPTION SPECTROSCOPY; DIMERS; DIPOLE MOMENTS; ELECTRONIC STRUCTURE; INFRARED SPECTRA; MOLECULAR STRUCTURE; POTENTIALS; RUBIDIUM; SEMICLASSICAL APPROXIMATION; SIMULATION; SURFACES; TEMPERATURE GRADIENTS; TEMPERATURE RANGE 0400-1000 K; VAPORS; WAVELENGTHS

Citation Formats

Beuc, R., Movre, M., Horvatic, V., Vadla, C., Dulieu, O., and Aymar, M. Absorption spectroscopy of the rubidium dimer in an overheated vapor: An accurate check of molecular structure and dynamics. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.032512.
Beuc, R., Movre, M., Horvatic, V., Vadla, C., Dulieu, O., & Aymar, M. Absorption spectroscopy of the rubidium dimer in an overheated vapor: An accurate check of molecular structure and dynamics. United States. doi:10.1103/PHYSREVA.75.032512.
Beuc, R., Movre, M., Horvatic, V., Vadla, C., Dulieu, O., and Aymar, M. Thu . "Absorption spectroscopy of the rubidium dimer in an overheated vapor: An accurate check of molecular structure and dynamics". United States. doi:10.1103/PHYSREVA.75.032512.
@article{osti_20982309,
title = {Absorption spectroscopy of the rubidium dimer in an overheated vapor: An accurate check of molecular structure and dynamics},
author = {Beuc, R. and Movre, M. and Horvatic, V. and Vadla, C. and Dulieu, O. and Aymar, M.},
abstractNote = {Experimental studies of the absorption spectrum of the Rb{sub 2} dimer are performed in the 600-1100 nm wavelength range for temperatures between 615 and 745 K. The reduced absorption coefficient is measured by spatially resolved white light absorption in overheated rubidium vapor with a radial temperature gradient, which enables simultaneous measurements at different temperatures. Semiclassical and quantum spectral simulations are obtained by taking into account all possible transitions involving the potential curves stemming from the 5 {sup 2}S+5 {sup 2}S and 5 {sup 2}S+5 {sup 2}P asymptotes. The most accurate experimental potential curves are used where available, and newly calculated potential curves and transition dipole moments otherwise. The overall consistency of the theoretical model with the experimental interpretation is obtained only if the radial dependence of both the calculated transition dipole moments and the spin-orbit coupling is taken into account. This highlights the low-resolution absorption spectroscopy as a valuable tool for checking the accuracy of molecular electronic structure calculations.},
doi = {10.1103/PHYSREVA.75.032512},
journal = {Physical Review. A},
number = 3,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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