Subject: Fe atom typing for MM2 in Spartan

From: Hiroshi Ogura <[email-masked]>
Date: Mon, 27 Nov 1995 14:50:19 -0700 (MST)

Is iron typed in the MM2 implementation for Spartan?  Allinger did assign
50 to the metals in general, but it seems as though the assignment is
not being made in the software. 

I obtained the MM2 parameters for iron porphyrins from Munro et al.,
J.Am.Chem.Soc., 1992, 114, 7218.  I wrote them into my parameter file, and
then I attempted to do a calculation on iron octamethyl tetraphenyl
porphyrin.  The software gave me an error message:  it said that the iron
was untyped.  It seems that Spartan did not recognize the type-50 atoms in
the parameter file. 

Have any of you attempted a MM2 calculation on a metal complex, using
Spartan?  If so, did you have a problem with the metal atom typing?  Were
you able to get around the problem?  Thanks in advance. 

p.s.  Thanks to all of you who gave me informations on the PM3 parameters
for iron!  As for the multiplicity problem, I have followed the people's
suggestions and checked the charge of the molecule and the number of
electrons.  They looked fine, and therefore I'm still stuck with the
problem.  This afternoon, I'm going to show the problem to a friend who is
very familiar with Spartan.  I'm hoping that we'd be able to find the
solution then. 

--
Hiroshi Ogura          | One man, he drinks up his whiskey;
[email-masked]  | Another, he drinks up his wine.
Dept. Chem., Univ. Az. | And they'll drink till their eyes are red with hate
Tucson, AZ 85721       | For those of a different kind. -- Richard Thompson