CCL:G: how to build a polythiophene unit cell for a pbc gaussian calculation



Hi Daniel

Remember me? I went to Chihuahua a couple of times with the CIP team. OK about your question. You can do this also if you have Gaussview in the following way:
Build your repeating unit of thiophene in terms of an assymetric unit (I'm assuming two would be fine to get one S atom pointing in one direction and another pointing in the opposite one). Delete one Hydrogen atom in alpha positions to an S atom and replace the other one (the symmetry related one) with a carbon atom.
Then go to EDIT -> PBC This will open a dialog window.
On the first tab (Symmetry) select Lattice Dimensions =1 (you  may activate line group symmetry and constraints)
On the second tab (Cell) click on the button "Place" This will allow you to move and define your translation vector Tv (make sure Location has the option "Atom" selected) There you see Vertex: O(0) Click on the Dummy atom and this should place the origin of the Tv on it. Then change Vertex to a(1) and click on the "naked C" atom at the other end of the molecule, this will now place the end of the vector at it.
On the third tab (View) you may now replicate the cell backwards and forwards by increasing the number in both the a and -a directions, respectively.
On the fourth tab (contents) delete the extra C atom you placed on step one.

Check also the Gaussview help at gaussian.com. It should be located under tech support.

I hope this helps!

Please say hi to your group

Joaquin
 
====================================================
Joaquin Barroso-Flores, Ph. D.
Facultatea de Chimie, Universitatea Babes-Bolyai
Cluj-Napoca, Romania

-> http://joaquinbarroso.com
-> http://joaquinbarroso.wordpress.com


joaquinbarroso''a''chem.ubbcluj.ro
joaquin.barroso''a''gmail.com


"Blogastronomía": http://joaquinbarroso.blogspot.com
====================================================



De: Daniel Glossman-Mitnik dglossman+*+gmail.com <owner-chemistry*_*ccl.net>
Para: "Flores, Joaquin Barroso " <joaco_barroso*_*yahoo.com>
Enviado: sábado, 5 de diciembre, 2009 2:48:49
Asunto: CCL:G: how to build a polythiophene unit cell for a pbc gaussian calculation


Dear netters:

I will be pleased if you can point me to a (step by step) guide on how to build a polythiophene
unit cell for a pbc gaussian calculation, using GaussView or any other program.
Please note: I don´t need only the input file, I want to learn how to build the unit cell.

Thanks in advance,

Daniel

***************************************************************************************************************
Dr. Daniel Glossman-Mitnik:
Centro de Investigación en Materiales Avanzados, SC
Grupo NANOCOSMOS  -  Modelado Molecular y Simulación Computacional de Nanomateriales
Miguel de Cervantes 120 - Complejo Industrial Chihuahua - Chihuahua, Chih 31109, Mexico
Phone: +52 614 4391151     Secretary/FAX: +52 614 4394852     Lab: +52 614 4394805
E-mail:  daniel.glossman++cimav.edu.mx          dglossman++gmail.com
WWW:  http://www.cimav.edu.mx/cv/daniel.glossman
             http://blogs.cimav.edu.mx/daniel.glossman
***************************************************************************************************************



¡Encuentra las mejores recetas
con Yahoo! Cocina!
http://mx.mujer.yahoo.com/cocina/