From tripos!metis!matt@uunet.uu.net  Thu Dec  8 19:18:21 1994
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From: tripos!metis!matt@uunet.uu.net (Matt Clark)
Message-Id: <9412082253.AA25924@metis.UUCP>
To: "Charles G. James" <uunet!unca.edu!JAMES@uunet.uu.net>
Cc: uunet!ccl.net!chemistry@uunet.uu.net
Subject: Re: CCL:Z matrix to cartesian coord. Question 
In-Reply-To: Your message of Thu, 08 Dec 94 14:27:17 -0500.
Date: Thu, 08 Dec 94 16:53:20 EST


In general you are correct, no methods require that kind of accuracy.

However I have found that having the exact same geometry for molecules
is necessary for comparing results in the same program, or among different
programs. I know of several cases where the truncation of decimal places
in file formats can change the results of a calculation, and sometimes
alter the path of a minimization when the starting structure is not 
close to a minimum.