Subject: re: CCL:MMFF94 validation in Sybyl and Cerius2

From: [email-masked] (Joe M Leonard)
Date: Thu, 24 Jun 1999 10:13:44 -0400

"Dr Adrian Stevens" <[email-masked]> writes:

>Has anyone checked the implementation of the MMFF94 force field in both
>Sybyl and Cerius2?

I cannot speak for Cerius2, but Sybyl's implementation of MMFF94
and MMFF94s pass the validation tests in CCL's archives.  The
MMFF94 implementation was revalidated recently, as there were
additions since last summer.  As Tom Halgren requested, this
information was sent to him when it was done.

I am unaware of any Sybyl user which independently performed the
validation tests, but would gladly assist such an effort.  I am
aware of similar validation being done by Wavefunction and
(now) Schrodinger.  I assume that any commercial software package
offering MMFF94/MMFF94s has examined the validation suites as
well.

I do not think that the latest MMFF94/MMFF94s information (the
various parameters mentioned in Halgren's last email on this)
has been made available in the CCL's archive, so it is possible
that there are structures which contains features not-well-
represented in the validation suites.  Such cases might yield
small differences due to implementation decisions, but these
(I think) would not be significant.

I think it is in everybody's best interest to have all implementations
of MMFF94/MMFF94s yield "the same" information.  If there are
questions with particular implementations, please feel free to
contact the respective companies - such concerns will be addressed
with all resonable dispatch...

Joe Leonard
[email-masked]