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Dislocation theory of chirality-controlled nanotube growth.

ABSTRACT: The periodic makeup of carbon nanotubes suggests that their formation should obey the principles established for crystals. Nevertheless, this important connection remained elusive for decades and no theoretical regularities in the rates and product type distribution have been found. Here we contend that any nanotube can be viewed as having a screw dislocation along the axis. Consequently, its growth rate is shown to be proportional to the Burgers vector of such dislocation and therefore to the chiral angle of the tube. This is corroborated by the ab initio energy calculations, and agrees surprisingly well with diverse experimental measurements, which shows that the revealed kinetic mechanism and the deduced predictions are remarkably robust across the broad base of factual data.

SUBMITTER: Ding F

PROVIDER: S-EPMC2637275 | biostudies-literature | 2009 Feb

REPOSITORIES: biostudies-literature

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Dislocation theory of chirality-controlled nanotube growth.

Ding Feng F Harutyunyan Avetik R AR Yakobson Boris I BI

Proceedings of the National Academy of Sciences of the United States of America 20090206 8

The periodic makeup of carbon nanotubes suggests that their formation should obey the principles established for crystals. Nevertheless, this important connection remained elusive for decades and no theoretical regularities in the rates and product type distribution have been found. Here we contend that any nanotube can be viewed as having a screw dislocation along the axis. Consequently, its growth rate is shown to be proportional to the Burgers vector of such dislocation and therefore to the c ...[more]

PMID: 19202071

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