Dear George, To get a numpy array with the coordinates of each site, you can use np.array([sys.pos(i) for i in range(sys.graph.num_nodes)]) for a finalized system. It is up to you to transform this into any other desired format. Best, Anton On Thu, Feb 19, 2015 at 10:58 PM, George Yumnam <georgeyumnam@gmail.com> wrote:

Dear Prof. Anton,

For a simple case, say after generating a Graphene sheet. I can plot it using kwant.plot(sys) and I can see the structure on the graphic window but I am not able to access this structure in any other way. I would like to obtain positions of each carbon atoms in a file so that it can be visualized in softwares like Vesta and Crystalmaker. So the preferred format is ".xyz" format, something like the one I have attached with this email. I understand that kwant is a package to perform quantum transport numerically. But I want to access the structures, created before the calculations, for analyzing if it is the desired structure for my problem.

Sincerely, George Yumnam