Hydrogen confined in single-wall carbon nanotubes: Anisotropy effects on ro-vibrational quantum levels

The energy levels of a hydrogen molecule embedded in the cavity of single-walled carbon nanotubes with different morphologies are studied using quantum dynamics simulations. All degrees of freedom of the confined molecule are explicitly included in our model, revealing that the vibrational motion is notably affected by the presence of a confining potential. The most relevant effects are nevertheless found in the rotational motion of the molecule and the appearance of a quantized translational motion. We further analyze the dependence of the confinement effects on the interaction potential, considering different parameters for the carbon-hydrogen interaction.