A study is presented of the effects of gas (especially H2) absorption within
the interstitial channels of a bundle of carbon nanotubes. The ground state of
the system is determined by minimizing the total energy, which includes the
molecules' interaction with the tubes, the inter-tube interaction, and the
molecules' mutual interaction (which is screened by the tubes). The
consequences of swelling include a significant increase in the gas uptake and a
3 per cent increase in the tubes' breathing mode frecuency.Comment: 4 page
