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Title: Modeling study of rotational relaxation and absorption

Abstract

The rate of rotational relaxation can influence the amount of single-line absorption for a transition that involves discrete rotational states. The extent of selected-state laser chemistry can thus be affected by the rotational bottleneck effect. Models of rotational relaxation and pulsed single-line absorption were constructed to determine the main factors governing the bottleneck effect, to determine the relaxation rate constants necessary to maintain equilibrium for a wide range of conditions, and to investigate the effects of rotational relaxation in a two-step photodissociative isotope enrichment scheme. Coupling the models with laboratory experiments could also yield a new method for determining rotational relaxation rates.

Authors:
;
Publication Date:
Research Org.:
Aerospace Corp., El Segundo, CA (USA). Chemistry and Physics Lab.
OSTI Identifier:
7331494
Report Number(s):
ATR-77(8127)-3
DOE Contract Number:
EY-76-C-03-1017
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; LASER ISOTOPE SEPARATION; ROTATIONAL STATES; RELAXATION; ABSORPTION; ENERGY-LEVEL TRANSITIONS; LASER RADIATION; MATHEMATICAL MODELS; ELECTROMAGNETIC RADIATION; ENERGY LEVELS; EXCITED STATES; ISOTOPE SEPARATION; RADIATIONS; SEPARATION PROCESSES; 050503* - Nuclear Fuels- Uranium Enrichment- Laser Excitation- (-1989); 400203 - Isotope Exchange & Isotope Separation- (-1987)

Citation Formats

Hwang, W.C., and Kamada, R.F.. Modeling study of rotational relaxation and absorption. United States: N. p., 1977. Web. doi:10.2172/7331494.
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Hwang, W.C., & Kamada, R.F.. Modeling study of rotational relaxation and absorption. United States. doi:10.2172/7331494.
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Hwang, W.C., and Kamada, R.F.. Thu . "Modeling study of rotational relaxation and absorption". United States. doi:10.2172/7331494. https://www.osti.gov/servlets/purl/7331494.
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@article{osti_7331494,
title = {Modeling study of rotational relaxation and absorption},
author = {Hwang, W.C. and Kamada, R.F.},
abstractNote = {The rate of rotational relaxation can influence the amount of single-line absorption for a transition that involves discrete rotational states. The extent of selected-state laser chemistry can thus be affected by the rotational bottleneck effect. Models of rotational relaxation and pulsed single-line absorption were constructed to determine the main factors governing the bottleneck effect, to determine the relaxation rate constants necessary to maintain equilibrium for a wide range of conditions, and to investigate the effects of rotational relaxation in a two-step photodissociative isotope enrichment scheme. Coupling the models with laboratory experiments could also yield a new method for determining rotational relaxation rates.},
doi = {10.2172/7331494},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Jan 20 00:00:00 EST 1977},
month = {Thu Jan 20 00:00:00 EST 1977}
}
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Technical Report:
View Technical Report (1.94 MB)
DOI:  10.2172/7331494
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