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arXiv · 1210.2523

4He adsorbed outside a single carbon nanotube

M. C. Gordillo·J. Boronat
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Abstract

The phase diagrams of $^4$He adsorbed on the external surfaces of single armchair carbon nanotubes with radii in the range 3.42 -- 10.85 Å\ are calculated using the diffusion Monte Carlo method. For nanotubes narrower than a (10,10) one, the ground state is an incommensurate solid similar to the one found for H$_2$ on the same substrates. For wider nanotubes, the phase with the minimum energy per particle is a liquid layer. Curved $\sqrt 3 \times \sqrt 3$ registered solids similar to the ones found on graphene and graphite were unstable for all the tubes considered.

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M. C. Gordillo, J. Boronat. 2012-10-09. 4He adsorbed outside a single carbon nanotube. https://doi.org/10.1103/physrevb.86.165409

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