By means of ab initio and tight-binding calculations it is shown that metastable nitrogen clusters N_8 (boats) can form quasi-one-dimensional ensembles in which the nearest clusters N_8 are bound to each other by covalent bonds. Those ensembles are characterized by rather high energy barriers (~ 0.3 eV) that prevent the fission of the ensembles into isolated N_8 clusters and/or N_2 molecules.
@article{arxiv.cond-mat/0204605,
title = {Metastable quasi-one-dimensional ensembles of nitrogen clusters N_8},
author = {N. N. Degtyarenko and V. F. Elesin and L. A. Openov and A. I. Podlivaev},
journal= {arXiv preprint arXiv:cond-mat/0204605},
year = {2009}
}