Thank You very much Felix Hanke. I did all the steps that you instructed. I just want to know the logic behind the repeat unit cells of C=200. How C=200 creates a length of 500nm. Or is there any other link describing about this.
Hi, once you have built the original small CNT structure, you have to see how large the unit cell is in the periodic direction before repitition. Use the lattice parameters dialog for this - accessed via Build | Symmetry | Lattice parameters on the menu or via the quick access button on the symmetry toolbar. Once you know the original length, you'll find out how many multiples of the original unit cell are required to get your desired overall length. All the best, Felix