Existence of novel quasi-one-dimensional phases of atoms adsorbed on the exterior surface of close-ended single wall nanotube bundles

We present results of adsorption measurements for Xe and Ax which confirm experimentally the formation of one-dimensional phases for these gases when adsorbed on the outer surfaces of close-ended single-wall carbon nanotube (SWNT) bundles. The existence of such phases had been predicted in recent computer simulations, but had remained, until the present work, unconfirmed. Experimental results for Xe and Ar on close-ended bundles of SWNT's are compared to, and found in substantial quantitative agreement with, those obtained in the computer simulation studies. The characteristics of the phases formed appear to be strongly influenced by steric effects.