Effect of rotational excitation of H-2 on isotopic exchange reaction with OD- at low temperatures

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F18%3A10386161" target="_blank" >RIV/00216208:11320/18:10386161 - isvavai.cz</a>

Result on the web

<a href="https://doi.org/10.1051/0004-6361/201833264" target="_blank" >https://doi.org/10.1051/0004-6361/201833264</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1051/0004-6361/201833264" target="_blank" >10.1051/0004-6361/201833264</a>

Result language

angličtina

Original language name

Effect of rotational excitation of H-2 on isotopic exchange reaction with OD- at low temperatures

Original language description

Aims. This paper presents experimentally obtained rate coefficients for the weakly endothermic reaction OD- + H-2 -&gt; OH- + HD with ortho- and para-hydrogen at astrophysically relevant temperatures between 10 and 300 K. Methods. The reaction was studied with normal and para-enriched (99.5% para-H-2) hydrogen in a 22-pole ion trap. The measured temperature dependencies of reaction rate coefficients are analyzed using a model which assumes that the rotational energies of the two reactants are equivalent to the translational energy in driving the reaction. Results. At room temperature, the rate coefficients of reactions with both nuclear spin variants reach 7 x10(-11) cm(3) s(-1), which is in good agreement with the previous results from ion trap and swarm experiments with normal hydrogen. Cooling down the trap slows down the reaction and leads, at a nominal trap temperature of 11 K, to a rate coefficient below 10(-14) cm(3) s(-1) for paraenriched hydrogen. The fitted reaction endothermicity of 25.3 +/- 2.2 meV agrees well with the literature value calculated in the Born-Oppenheimer approximation, Delta H degrees = 24.0 meV. A simpler evaluation procedure, fitting the data with Arrhenius functions, results in (p)k = 16.8 x10(-11) exp(-234 K/T) cm(3) s(-1) for pure para-hydrogen and degrees k= 9.4 x 10(-11) exp(-101 K/T) cm(3) s(-1) for pure orthohydrogen.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10305 - Fluids and plasma physics (including surface physics)

Project

<a href="/en/project/GA17-19459S" target="_blank" >GA17-19459S: Reactions of ions with atomic deuterium - experimental study with astrophysical implications</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2018

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Astronomy &amp; Astrophysics [online]

ISSN

1432-0746

e-ISSN

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Volume of the periodical

615

Issue of the periodical within the volume

Jul

Country of publishing house

FR - FRANCE

Number of pages

5

Pages from-to

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UT code for WoS article

000439527100001

EID of the result in the Scopus database

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