Hi, QE package performs calculation with periodic cell. if you want to do non-periodic calculations , you should set up supercell with large vacuum seperations between the periodic images.
With respect to carbon nanotubes, you can define ibrav to 6 with certain values for celldm(1) and celldm(3), such as celldm(1)=47.243171944358878, celldm(3) =0.1704 for zigzag nanotube. If you want to simulate finite carbon nanotubes, what you need is to define some value along longitudinal direction. Regards, On Fri, Dec 12, 2008 at 3:50 PM, Reza Kalantari < rezakalantarinezhad at gmail.com> wrote: > Dear Paolo Giannozzi > > Thank you so much for your attention. I have seen Marzari's group > simulations on carbon nanotube which were done with Quantum-Espresso but all > examples of Quantum-Espresso on its official website are for periodic mater > so I don't have a sample input file for a non-periodic simulation. > Where can I find an input sample file (pw.x input file) for a non-periodic > simulation? > How should I define ibrav | celldm | assume_isolated? > Should I define CELL_PARAMETERS ? > I try to calculate electronic structure of a carbon nanotube when another > biomolecule dock with it. have seen ever such as this by Quantum-Espresso? I > want to know that it's a conceptual barrier to this purpose with > Quantum-Espresso? > Thank you very much again for you attention. I have started working on this > subject recently so maybe my questions are rudimentary so sorry. > > Reza Kalantari-Nezhad > PhD Student > Amir Kabir University of Technology > rezakalantarinezhad at gmail.com > rkalantari at aut.ac.ir > > > On Thu, Dec 11, 2008 at 4:34 PM, Paolo Giannozzi <giannozz at > democritos.it>wrote: > >> On Dec 11, 2008, at 7:29 , Reza Kalantari wrote: >> > I know that I should use supercell for this purpose but I don't >> > know how can I do it? >> > >> there is no conceptual difference between a so-called "supercell" and >> a crystal cell. >> > Have you seen ever such as this simulation by Quantum-Espresso? >> > >> like this? http://web.mit.edu/newsoffice/2006/nanotubes.html >> >> P. >> --- >> Paolo Giannozzi, Democritos and University of Udine, Italy >> >> >> _______________________________________________ >> Pw_forum mailing list >> Pw_forum at pwscf.org >> http://www.democritos.it/mailman/listinfo/pw_forum >> > > > > -- > Eradatmand > Reza Kalantari Nezhad > PhD Student > Mechanical Engineering > Amir Kabir University of Technology (Tehran Polytechnic) > Tehran > Iran > > > Mobile Phone: 0098-935-2578543 > > > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://www.democritos.it/mailman/listinfo/pw_forum > > -- Hai-Ping Lan Department of Electronics , Peking University , Bejing, 100871 lanhaiping at gmail.com, hplan at pku.edu.cn -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20081212/248c7809/attachment.htm
