We study the energetics of acetylene (C2H2) molecules inside a carbon nanotube (CNT) using the {\it ab initio} pseudopotential method. The encapsulation energy of a single C2H2 molecule into the nanotube and the formation energy of (C2H2)n@CNT are calculated. We investigate whether a polyacetylene chain can be produced by fusion of the close-packed acetylene molecules inside the CNT and find that there is practically no activation barrier to polymerization. We propose to employ this method to obtain straight, perfectly isolated, and single-stranded polyacetylene chains encapsulated inside CNTs, which may be used for molecular electronic devices.
@article{arxiv.cond-mat/0506748,
title = {Encapsulation and polymerization of acetylene molecules inside a carbon nanotube},
author = {Gunn Kim and Yeonju Kim and Jisoon Ihm},
journal= {arXiv preprint arXiv:cond-mat/0506748},
year = {2016}
}