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 yo= u have Gaussview in the following way:
Build your repeating unit of thio= phene 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 (Symmet= ry) select Lattice Dimensions =3D1 (you may activate line group symme= try 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) C= lick on the Dummy atom and this should place the origin of the Tv on it. Th= en change Vertex to a(1) and click on the "naked C" atom at the other end o= f 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 i= ncreasing the number in both the a and -a directions, respectively.
On t= he 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 un= der tech support.

I hope this helps!

Please say hi to your g= roup

Joaquin

=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
Joaquin Barroso-Flores,= Ph. D.
Facultatea de Chimie, Universitatea Babes-Bolyai
Cluj-Napoca,= Romania

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

joaqu= inbarroso''a''chem.ubbcluj.ro
joaquin.barroso''a''gmail.com

"Blogastronom=EDa": http://joaquinbarroso.blogspot.com
= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D

<= hr size=3D"1">De: Daniel G= lossman-Mitnik dglossman+*+gmail.com <owner-chemistry*_*ccl.net>
= Para: "Flores, Joaquin Barros= o " <joaco_barroso*_*yahoo.com>
E= nviado: s=E1bado, 5 de diciembre, 2009 2:48:49
Asunto: CCL:G: how to build a polythioph= ene 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=B4t need only = the input file, I want to learn how to build the unit cell.
=0A
Thank= s in advance,

Daniel

**************************= ***************************************************************************= **********
Dr. Daniel Glossman-Mitnik:
Centro de Investigaci=F3n en M= ateriales Avanzados, SC
=0AGrupo NANOCOSMOS - Modelado Molec= ular y Simulaci=F3n Computacional de Nanomateriales
Miguel de Cervantes = 120 - Complejo Industrial Chihuahua - Chihuahua, Chih 31109, Mexico
Phon= e: +52 614 4391151 Secretary/FAX: +52 614 4394852 &nbs= p; Lab: +52 614 4394805
=0AE-mail: daniel.glossman++cimav.edu.mx = dglossman++gmai= l.com
WWW: http://www.cimav.edu.mx/cv/daniel.gl= ossman
=0A http://blogs.cimav.edu.mx/daniel.glossman
*********************= ***************************************************************************= ***************
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