From owner-chemistry@ccl.net Sun Apr 19 01:13:01 2015
From: "=?iso-8859-1?Q?V=EDctor_Lua=F1a?= Cabal victor * fluor.quimica.uniovi.es" <owner-chemistry : server.ccl.net>
To: CCL
Subject: CCL:G: The best molecule specification format
Message-Id: <-51269-150418160139-3869-DdNiNVF1h5ITXy3u3AFQxA : server.ccl.net>
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Date: Sat, 18 Apr 2015 21:54:33 +0200
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Sent to CCL by: =?iso-8859-1?Q?V=EDctor_Lua=F1a?= Cabal [victor]^[fluor.quimica.uniovi.es]
On Sat, Apr 18, 2015 at 12:47:45PM -0400, Safiya Ess Amer amersaf85_-_yahoo.com wrote:
> 
> Sent to CCL by: "Safiya Ess Amer" [amersaf85.*.yahoo.com]
> Hi all
> I want to do geometry optimization of a system, what is the best molecule 
> specification format, Z-Matrix, Cartesian coordinates, or Mixed to do that?

Safiya,

1) Which is best depends on many things: the quantum code, your experience,
   your abilities as scientific programmer.

2) I remember you are using gaussian.

3) For the optimizers installed in gaussian using Z-matrix can be very
   efficient.

4) If you enjoy programming you will love to read the postg code, that is
   able to use gaussian as a routine to drive optimizations and other tasks.

5) Using symmetry and cartesian coordinates gives you all freedom, but
   it is not simple.

6) Remember: there is a steep ladder to scientific programming, but
   it pays at the end, ¡you become proficient in exploring math world!

7) In <http://en.wikipedia.org/wiki/Z-matrix_%28chemistry%29> there are
   good places to explore.

Best regards,
            Dr. Víctor Luaña
--
     .  .    DEEP THOUGHT in D. Adams; Hitchhikers Guide to the Galaxy:
    / `' \   "I think the problem, to be quite honest with you,
   /(o)(o)\  is that you have never actually known what the question is."
  /`. \/ .'\ 
 /   '`'`   \ "Lo mediocre es peor que lo bueno, pero también es peor
 |  \'`'`/  | que lo malo, porque la mediocridad no es un grado, es una
 |  |'`'`|  | actitud"
  \/`'`'`'\/          -- Jorge Wasenberg, 2015
===(((==)))==================================+=========================
! Dr.Víctor Luaña, in silico chemist & prof. ! Mediocre is worse than
! Departamento de Química Física y Analítica ! good, but it is also
! Universidad de Oviedo, 33006-Oviedo, Spain ! worse than bad, because
! e-mail:   victor*fluor.quimica.uniovi.es   ! mediocrity is not a grade,
! phone: +34-985-103491  fax: +34-985-103125 ! it is an attitude
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