Thermodynamic stability and electronic structure of small carbon nitride nanotubes

In order to tune the electronic properties of carbon-based nanotubes, attention is now turning to new avenues based on chemical manipulation. The introduction of nitrogen at either doping or alloying concentrations has been shown to give rise to new tubular structures and desirable electronic properties, but a detailed understanding of the strain and thermodynamic properties is still lacking. In this paper a systematic computational study of the structure and thermodynamics of small C_xN nanotubes is presented (x = 1, 2, 3, 5, and 7). The aim of this work is to investigate which stoichiometries and atomic distributions are likely to be stable under ambient and operating conditions, thereby offering viable candidates for future synthesis efforts. In addition to this, the electronic properties of stable structures are briefly examined, to establish whether small carbon nitride nanotubes may be tailored for emerging technological applications.