Subject: Re: CCL:semantics : molecular modelling

From: "Lestaw K. Bieniasz" <[email-masked]>
Date: Tue, 17 Jun 1997 20:05:44 +0200 (W. Europe Daylight Time)

Tuebingen, 17.06.97

On Tue, 17 Jun 1997, Jeffrey L. Nauss wrote:

> The immediate question that comes into my mind with Alexandre's
> statement is: what is "computational chemistry?"  Why is there a
> distinction between computational chemistry and molecular modelling?
> 
> I have resolved the issue in my own mind as follows.  Computational
> chemistry would be the application of numerical calculations to the
> study of molecular structure.  Thus I would include in that definition

> Thus I consider computational chemistry to be a subset of the more
> general field of molecular modelling.  Molecular modelling in itself may
> not involve any computations.  But computational chemistry must.

I would suggest that you have a look at the introductions to "Reviews of
Computational Chemistry". A definition of computational chemistry is
provided in one of the volumes (I do not remember now which one, sorry,
but you will easily find it). According to this definition, everything
that requires the use of computers in chemical research, is computational
chemistry. Application of numerical calculations to the study of molecular
structures would be one of such areas of investigations. However, there
are also other, like for example "classical" chemical kinetic
computations, which assume a "continuum" approximation to the matter, and
hence no molecular structure considerations are involved. Such
computations are often very sophisticated and computationally demanding,
and there is no reason to consider them less important or less difficult
than quantum mechanical calculations. Similar examples occur let's say
in electrochemical kinetic modelling which is my area of interest. 
Yet another examples are provided by the paper of Larter and Showalter
in volume 10 of the above reviews.

In my opinion the above definition of computational chemistry is the only
one that should be used, and it removes a certain pathology from the
contemporary practice in computational chemistry, which has been dominated
by quantum chemical calculations. Such calculations are certainly
important, but there are other areas which should also find their right
place in the computational chemistry. If you are not convinced, look
at computational physics. Physicists do not put an equality sign between
quantum physics and computational physics.

Sincerely,

					L.Bieniasz

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|                        Dr. Leslaw Bieniasz                        |
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