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Title: Spatial Diffusion of Hydrogen Atoms in Normal and Para-Hydrogen Molecular Films at Temperature 0.7 K
We report on electron spin resonance studies of H atoms stabilized in solid H2 films at temperature 0.7 K and in a magnetic field of 4.6 T. The H atoms were produced by bombarding H2 films with 100 eV electrons from a radiofrequency discharge run in the sample cell. We observed a one order of magnitude faster H atom accumulation in the films made of para-H2 gas with a small ortho-H2 concentration (0.2% ortho-H2 ) as compared with those made from normal H2 gas content (75% ortho-H2 ). We also studied the influence of ortho-H2 molecules on spatial diffusion of H atoms in solid H2 films. The spatial diffusion of H atoms in both normal and para-H2 films is faster than the diffusion obtained from the measurement of H atom recombination. The rate of spatial diffusion of H atoms in para-H2 films was slower in comparison with that in the normal H2 films. We discuss possible explanations of these observations.  more » « less
Award ID(s):
2104756
PAR ID:
10498013
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Springer
Date Published:
Journal Name:
Journal of Low Temperature Physics
Volume:
215
ISSN:
0022-2291
Subject(s) / Keyword(s):
Solid molecular hydrogen. Hydrogen atoms. Diffusion. Electron spin resonance.
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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