GECOOR
Generator of armchair nanotubes with specific bond lengths and angles
...Due to this, a simple-to-use program is implemented within a command-line, for both Linux and MS Windows environments, to generate atomic coordinate files for later use in first-principles simulation codes. The program considers monatomic armchair nanotubes, and the geometric parameters considered are: the length of the bonds perpendicular to the tube axis, the length of the non-perpendicular bonds, and the angle between two non-perpendicular bonds."