Quench deposited Kr-H₂ and Ar-H₂ mixtures: in quest of impurity-hydrogen gels

The structure and morphology of low-temperature quench condensed binary alloys of hydrogen with argon and krypton were studied by the powder x-ray diffraction. The nominal hydrogen fraction c in both systems was varied from 0 to 50%; the condensation was performed at 5-6 K; both as-prepared and anne...

Повний опис

Збережено в:
Бібліографічні деталі
Опубліковано в: :Физика низких температур
Дата:2003
Автори: Strzhemechny, M.A., Galtsov, N.N., Prokhvatilov, A.I.
Формат: Стаття
Мова:Англійська
Опубліковано: Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України 2003
Теми:
Онлайн доступ:https://nasplib.isofts.kiev.ua/handle/123456789/128867
Теги: Додати тег
Немає тегів, Будьте першим, хто поставить тег для цього запису!
Назва журналу:Digital Library of Periodicals of National Academy of Sciences of Ukraine
Цитувати:Quench deposited Kr-H₂ and Ar-H₂ mixtures: in quest of impurity-hydrogen gels / M.A. Strzhemechny, N.N. Galtsov, A.I. Prokhvatilov // Физика низких температур. — 2003. — Т. 29, № 6. — С. 699-705. — Бібліогр.: 18 назв. — англ.

Репозитарії

Digital Library of Periodicals of National Academy of Sciences of Ukraine
_version_ 1862746276877041664
author Strzhemechny, M.A.
Galtsov, N.N.
Prokhvatilov, A.I.
author_facet Strzhemechny, M.A.
Galtsov, N.N.
Prokhvatilov, A.I.
citation_txt Quench deposited Kr-H₂ and Ar-H₂ mixtures: in quest of impurity-hydrogen gels / M.A. Strzhemechny, N.N. Galtsov, A.I. Prokhvatilov // Физика низких температур. — 2003. — Т. 29, № 6. — С. 699-705. — Бібліогр.: 18 назв. — англ.
collection DSpace DC
container_title Физика низких температур
description The structure and morphology of low-temperature quench condensed binary alloys of hydrogen with argon and krypton were studied by the powder x-ray diffraction. The nominal hydrogen fraction c in both systems was varied from 0 to 50%; the condensation was performed at 5-6 K; both as-prepared and annealed samples were examined by the x-ray diffraction. Few, often only one reflection can be unambiguously detected for the as-grown alloy samples. In the Kr-H₂ condensates with c < 10%, the x-ray patterns show fine-grain krypton-rich crystallites with rather high actual hydrogen contents as estimated from Vegard`s law. At high nominal hydrogen fractions( %) c ≥ 10 , no the reflections attributable to the krypton lattice were recorded and the incoherent background showed no characteristic swelling around the position of reflection (111) from pure Kr but, instead, the reflections from a hydrogen-rich hcp phase were distinct. As the temperature was steadily raised, first the hydrogen reflections disappeared and then, at a certain temperature, the samples underwent an abrupt transformation, releasing heat and making the krypton component forms larger, x-ray detectable textured crystallites. In the as-grown Ar-H₂ samples, only (111) reflections from the argon-rich phase were recorded. Warmup led to the same consequences, viz., effusion of hydrogen and then recrystallization. In both systems, the recrystallization onset temperature depends substantially on the nominal hydrogen fraction in the gas. The shift of the lattice parameter in the as-grown argon-based phases suggests a strong suppression of the quantum nature of hydrogen in argon lattice environment. The entire set of the experimental findings can be treated as evidence that the quench-condensed hydrogen-containing alloys morphologically resemble helium-impurity solids (gels) whose structure and morphology are currently studied at Cornell University.
first_indexed 2025-12-07T20:44:59Z
format Article
fulltext
id nasplib_isofts_kiev_ua-123456789-128867
institution Digital Library of Periodicals of National Academy of Sciences of Ukraine
issn 0132-6414
language English
last_indexed 2025-12-07T20:44:59Z
publishDate 2003
publisher Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України
record_format dspace
spelling Strzhemechny, M.A.
Galtsov, N.N.
Prokhvatilov, A.I.
2018-01-14T11:01:11Z
2018-01-14T11:01:11Z
2003
Quench deposited Kr-H₂ and Ar-H₂ mixtures: in quest of impurity-hydrogen gels / M.A. Strzhemechny, N.N. Galtsov, A.I. Prokhvatilov // Физика низких температур. — 2003. — Т. 29, № 6. — С. 699-705. — Бібліогр.: 18 назв. — англ.
0132-6414
PACS: 61.10.-i, 61.43.Dq, 61.66 -f
https://nasplib.isofts.kiev.ua/handle/123456789/128867
The structure and morphology of low-temperature quench condensed binary alloys of hydrogen with argon and krypton were studied by the powder x-ray diffraction. The nominal hydrogen fraction c in both systems was varied from 0 to 50%; the condensation was performed at 5-6 K; both as-prepared and annealed samples were examined by the x-ray diffraction. Few, often only one reflection can be unambiguously detected for the as-grown alloy samples. In the Kr-H₂ condensates with c < 10%, the x-ray patterns show fine-grain krypton-rich crystallites with rather high actual hydrogen contents as estimated from Vegard`s law. At high nominal hydrogen fractions( %) c ≥ 10 , no the reflections attributable to the krypton lattice were recorded and the incoherent background showed no characteristic swelling around the position of reflection (111) from pure Kr but, instead, the reflections from a hydrogen-rich hcp phase were distinct. As the temperature was steadily raised, first the hydrogen reflections disappeared and then, at a certain temperature, the samples underwent an abrupt transformation, releasing heat and making the krypton component forms larger, x-ray detectable textured crystallites. In the as-grown Ar-H₂ samples, only (111) reflections from the argon-rich phase were recorded. Warmup led to the same consequences, viz., effusion of hydrogen and then recrystallization. In both systems, the recrystallization onset temperature depends substantially on the nominal hydrogen fraction in the gas. The shift of the lattice parameter in the as-grown argon-based phases suggests a strong suppression of the quantum nature of hydrogen in argon lattice environment. The entire set of the experimental findings can be treated as evidence that the quench-condensed hydrogen-containing alloys morphologically resemble helium-impurity solids (gels) whose structure and morphology are currently studied at Cornell University.
This work was supported by the CRDF (grant UP2-2445-KH-02). The authors thank V. V. Khmelenko for communicating results prior to publication and A. A. Solodovnik for valuable discussions.
en
Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України
Физика низких температур
3-й Международный семинар по физике низких температур в условиях микрогравитации
Quench deposited Kr-H₂ and Ar-H₂ mixtures: in quest of impurity-hydrogen gels
Article
published earlier
spellingShingle Quench deposited Kr-H₂ and Ar-H₂ mixtures: in quest of impurity-hydrogen gels
Strzhemechny, M.A.
Galtsov, N.N.
Prokhvatilov, A.I.
3-й Международный семинар по физике низких температур в условиях микрогравитации
title Quench deposited Kr-H₂ and Ar-H₂ mixtures: in quest of impurity-hydrogen gels
title_full Quench deposited Kr-H₂ and Ar-H₂ mixtures: in quest of impurity-hydrogen gels
title_fullStr Quench deposited Kr-H₂ and Ar-H₂ mixtures: in quest of impurity-hydrogen gels
title_full_unstemmed Quench deposited Kr-H₂ and Ar-H₂ mixtures: in quest of impurity-hydrogen gels
title_short Quench deposited Kr-H₂ and Ar-H₂ mixtures: in quest of impurity-hydrogen gels
title_sort quench deposited kr-h₂ and ar-h₂ mixtures: in quest of impurity-hydrogen gels
topic 3-й Международный семинар по физике низких температур в условиях микрогравитации
topic_facet 3-й Международный семинар по физике низких температур в условиях микрогравитации
url https://nasplib.isofts.kiev.ua/handle/123456789/128867
work_keys_str_mv AT strzhemechnyma quenchdepositedkrh2andarh2mixturesinquestofimpurityhydrogengels
AT galtsovnn quenchdepositedkrh2andarh2mixturesinquestofimpurityhydrogengels
AT prokhvatilovai quenchdepositedkrh2andarh2mixturesinquestofimpurityhydrogengels