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Dave,
The results sound intriguing.
However, without a journal publication or description of the method, this
information is largely useless to anyone hoping to do research with this
method and publish the results.
Is a journal article going to be
published? When? Where?
Mark
----- Original Message -----
Sent: Tuesday, September 11, 2001 12:40
PM
Subject: CCL:The PM5 method?
Dr James Stewart (author of MOPAC) gave a presentation on PM5
at the Chicago ACS on August 28, 2001.
He stated that PM5, now
includes ALL main group elements in one method, adding Li, Be, B, Na, Mg, K,
Ca, etc.
PM5 is also claimed to be significantly more accurate than
PM3 or AM1 for heats of formation. However, the actual improvement in accuracy
varies by element. The average unweighted errors in absolute heats of
formation (kcal/mol) for each method compared to experiment is approximately
as shown below. The averages are based on all elements previously published by
Stewart for PM3 and AM1, and for all main group elements for PM5. Of course,
relative errors are typically much
smaller.
AM1 16.4
kcals/mol
PM3 20.4
kcals/mol
PM5 5.6 kcals/mol
(preliminary results)
PM5 works with the COSMO solvation field and on
systems of up to 20,000 atoms when using the linear scaling
option.
Fujitsu is currently testing a beta version of PM5 at present.
The PM5 method will be available in CAChe at the end of this month
(September), and also in a new release of MOPAC 2002 in the near future, when
more information should become available.
David Gallagher
Fujitsu
(www.cachesoftware.com/cache5/)
At 06:36 AM
9/11/2001 -0700, Mark A. Thompson wrote:
Has the new "PM5" method been described in the literature
anywhere?
Mark
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