ESR investigation of hydrogen and deuterium atoms in impurity-helium solids

• Дата: 2003
• Автори: Kiselev, S.I., Khmelenko, V.V., Bernard, E.P., Lee, D.M.
• Формат: Стаття
• Мова: English
• Опубліковано: Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України 2003
• Назва видання: Физика низких температур
• Теми: 3-й Международный семинар по физике низких температур в условиях микрогравитации
• Онлайн доступ: http://dspace.nbuv.gov.ua/handle/123456789/128859
• Назва журналу: Digital Library of Periodicals of National Academy of Sciences of Ukraine
• Цитувати: ESR investigation of hydrogen and deuterium atoms in impurity-helium solids / S.I. Kiselev, V.V. Khmelenko, E.P. Bernard, D.M. Lee // Физика низких температур. — 2003. — Т. 29, № 6. — С. 678-683. — Бібліогр.: 22 назв. — англ.

Impurity-helium solids (Im-He solids) are porous solids created by injecting a beam of mixed helium and impurity gases into superfluid ⁴He. In this work we use electron spin resonance (ESR) techniques to investigate Im-He solids containing atoms and molecules of hydrogen and/or deuterium. We have performed studies of low temperature (T ~ 1.35 K) tunnelling chemical reactions in which deuterium atoms replace the hydrogen atoms bound in H₂ or HD molecules to produce large (up to 7.5×10¹⁷cm⁻³) and relatively stable concentrations of free hydrogen atoms. The time dependence of H and D atom concentrations has been investigated for Im-He samples with different initial ratios of hydrogen and deuterium ranging from 1:20 to 1:1.The satellite ESR lines associated with the dipolar coupling of electron spins of H and D atoms to the nuclear moments of the hydrogen nuclei found in neighboring molecules have been observed in Im-He solids. The forbidden hyperfine transition of atomic hydrogen involving the mutual spin flips of electrons and protons has also been observed.