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Updated: Feb 20, 2026
Resonance Raman Spectroscopy of Extreme Nanowires and Other 1D Systems
Published on: April 28, 2016
Quantum confinement of molecular deuterium clusters in carbon nanotubes: ab initio evidence for hexagonal close
María Pilar de Lara-Castells1, Andreas W Hauser, Alexander O Mitrushchenkov
1Instituto de Fsica Fundamental (C.S.I.C.), Serrano 123, E-28006, Madrid, Spain. Pilar.deLara.Castells@csic.es.
Abstract:
An ab initio study of quantum confinement of deuterium clusters in carbon nanotubes is presented. First, density functional theory (DFT)-based symmetry-adapted perturbation theory is used to derive parameters for a pairwise potential model describing the adsorbate-nanotube interaction. Next, we analyze the quantum nuclear motion of N D2 molecules (N < 4) confined in carbon nanotubes using a highly accurate adsorbate-wave-function-based approach, and compare it with the motion of molecular hydrogen. We further apply an embedding approach and study zero-point energy effects on larger hexagonal and heptagonal structures of 7-8 D2 molecules. Our results show a preference for crystalline hexagonal close packing hcp of D2 molecules inside carbon nanotubes even at the cost of a reduced volumetric density within the cylindrical confinement.
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