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Title: Lifetimes of Vibro-Rotational Levels in Excited Electronic States of Diatomic Hydrogen Isotopologues

Abstract

The current situation in studies of lifetimes of excited rovibronic levels for the H{sub 2}, D{sub 2}, T{sub 2}, HD, HT, and DT molecules is analyzed. All measured lifetime values (792 entries for 618 different vibro-rotational levels of 33 electronic states) reported in 61 publications before April 2015 are compiled and listed in tabular format together with an annotated bibliography. Experimental data are only available for the H{sub 2}, HD, and D{sub 2} molecules. The data collected in the present work show fragmentariness of experimental data. For the vast majority of the levels, the lifetime values were reported in one paper only and up to now are without independent experimental verification. A complete bibliography of publications concerning semiempirical determination and nonempirical calculations of the lifetimes is presented. Numerical results obtained in the framework of these two approaches are listed only in cases when experimental data are available. For more than half of the levels, the differences between measured and calculated values are three times higher than experimental errors. These discrepancies show necessity of more precise experimental and nonempirical studies. For some 79 rovibronic levels, our analysis makes it possible to propose certain set of recommended lifetime values.

Authors:
;  [1]
  1. Faculty of Physics, St. Petersburg State University, St. Petersburg 198504 (Russian Federation)
Publication Date:
OSTI Identifier:
22493958
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Physical and Chemical Reference Data; Journal Volume: 44; Journal Issue: 2; Other Information: (c) 2015 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS

Citation Formats

Astashkevich, S. A., E-mail: astashkevich@mail.ru, and Lavrov, B. P., E-mail: b.lavrov@spbu.ru. Lifetimes of Vibro-Rotational Levels in Excited Electronic States of Diatomic Hydrogen Isotopologues. United States: N. p., 2015. Web. doi:10.1063/1.4921434.
Astashkevich, S. A., E-mail: astashkevich@mail.ru, & Lavrov, B. P., E-mail: b.lavrov@spbu.ru. Lifetimes of Vibro-Rotational Levels in Excited Electronic States of Diatomic Hydrogen Isotopologues. United States. doi:10.1063/1.4921434.
Astashkevich, S. A., E-mail: astashkevich@mail.ru, and Lavrov, B. P., E-mail: b.lavrov@spbu.ru. 2015. "Lifetimes of Vibro-Rotational Levels in Excited Electronic States of Diatomic Hydrogen Isotopologues". United States. doi:10.1063/1.4921434.
@article{osti_22493958,
title = {Lifetimes of Vibro-Rotational Levels in Excited Electronic States of Diatomic Hydrogen Isotopologues},
author = {Astashkevich, S. A., E-mail: astashkevich@mail.ru and Lavrov, B. P., E-mail: b.lavrov@spbu.ru},
abstractNote = {The current situation in studies of lifetimes of excited rovibronic levels for the H{sub 2}, D{sub 2}, T{sub 2}, HD, HT, and DT molecules is analyzed. All measured lifetime values (792 entries for 618 different vibro-rotational levels of 33 electronic states) reported in 61 publications before April 2015 are compiled and listed in tabular format together with an annotated bibliography. Experimental data are only available for the H{sub 2}, HD, and D{sub 2} molecules. The data collected in the present work show fragmentariness of experimental data. For the vast majority of the levels, the lifetime values were reported in one paper only and up to now are without independent experimental verification. A complete bibliography of publications concerning semiempirical determination and nonempirical calculations of the lifetimes is presented. Numerical results obtained in the framework of these two approaches are listed only in cases when experimental data are available. For more than half of the levels, the differences between measured and calculated values are three times higher than experimental errors. These discrepancies show necessity of more precise experimental and nonempirical studies. For some 79 rovibronic levels, our analysis makes it possible to propose certain set of recommended lifetime values.},
doi = {10.1063/1.4921434},
journal = {Journal of Physical and Chemical Reference Data},
number = 2,
volume = 44,
place = {United States},
year = 2015,
month = 6
}
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