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Hindered rotation of H2 adsorbed interstitially in nanotube bundles

M. K. Kostov·H. Cheng·R. M. Herman·M. W. Cole·J. C. Lewis
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Abstract

A theoretical study on the rotational dynamics of H2 molecules trapped in the interstitial channels (ICs) of a carbon nanotube bundle is presented. The potential used in this study is modeled as a sum of atom-atom (C-H) van der Waals interactions and electrostatic interactions of the molecule with the surrounding nanotubes.The rotational energy spectra is calculated using a product wave function, where the coupling between translational and rotational modes is treated in a mean-field manner . Molecular dynamics (MD) simulation study was performed for estimating the hydrogen rotational barrier. Both theoretical calculations and simulation results reveal the existence of a large rotational barrier (~ 40 meV). The consequences of this rotational barrier for the rotational energy levels are worked out in detail.

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M. K. Kostov, H. Cheng, R. M. Herman, M. W. Cole, J. C. Lewis. 2001-10-12. Hindered rotation of H2 adsorbed interstitially in nanotube bundles. https://doi.org/10.1063/1.1424290

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