Infrared studies of ortho-para conversion at Cl-atom and H-atom impurity centers in cryogenic solid hydrogen
Vernadsky National Library of Ukraine
Переглянути архів Інформація| Поле | Співвідношення | |
| Title |
Infrared studies of ortho-para conversion at Cl-atom and H-atom impurity centers in cryogenic solid hydrogen
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| Creator |
Raston, P.L.
Kettwich, S.C. Anderson, D.T. |
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| Subject |
Nanostructures and Impurity Centers in Cryogenic Environment
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| Description |
We report infrared spectroscopic studies of H₂ ortho-para (o/p) conversion in solid hydrogen doped with Clatoms at 2 K while the Cl+H₂(v=1)→HCl+H infrared-induced chemical reaction is occurring. The Cl-atom doped hydrogen crystals are synthesized using 355 nm in situ photodissociation of Cl₂ precursor molecules. For hydrogen solids with high ortho-H₂ fractional concentrations (Xo=0.55), the o/p conversion kinetics is dominated by Cl-atom catalyzed conversion with a catalyzed conversion rate constant Kcc=1.16(11) min⁻¹ and the process is rate-limited by ortho-H₂ quantum diffusion. For hydrogen crystals with low ortho-H₂ concentrations (Xo=0.03), single-exponential decay of the ortho-H₂ concentration with time is observed which is attributed to H-atom catalyzed o/p conversion by the H-atoms produced during the infrared-induced Cl+H₂ reaction. The measured H-atom catalyzed o/p conversion kinetics indicates the H-atoms are mobile under these conditions in agreement with previous ESR measurements.
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| Date |
2017-05-19T09:06:26Z
2017-05-19T09:06:26Z 2010 |
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| Type |
Article
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| Identifier |
Infrared studies of ortho-para conversion at Cl-atom and H-atom impurity centers in cryogenic solid hydrogen / P.L. Raston, S.C. Kettwich, D.T. Anderson // Физика низких температур. — 2010. — Т. 36, № 5. — С. 495-503. — Бібліогр.: 31 назв. — англ.
0132-6414 PACS: 66.30.Ma, 67.80.F–, 67.80.dj http://dspace.nbuv.gov.ua/handle/123456789/117038 |
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| Language |
en
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| Relation |
Физика низких температур
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| Publisher |
Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України
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