Subject: Summary: Molecular mechanics (metals)

From: "G.P. Miscione" <[email-masked]>
Date: Wed, 24 Feb 1999 17:32:25 +0100

Hi all,

the following was my original question:

"could anybody please let me have info/advises on good 
molecular mechanics software package supporting 
transition metals?"

And below I listed all the answers i've received so far.
Thanks to everyone who replied to me: i did appreciate your help.

Best regards,
G.P. Miscione

--
From: Matthew F Schlecht <[email-masked]>

The PC-based modeling program PCMODEL has a good algorithm for
calculating the structure of transition metal compounds.
More information on it may be found at the Serena Software website at:

                        http://www.serenasoft.com/
--
From: [email-masked]

The Universal Force Field produced by MSI in San Diego is a good one.

--
From: "Dr. Klaus Stark" <[email-masked]>

with MSI's Discover or the OFF (Open Force Field) 
force field engine you can work with several force fields and
perform energy minimization, molecular dynamics and MD analysis. There are
basically two
force fields which can handle a great part of the periodic table. These are
the
so-called rule based force fields which rely on atomic parameters coupled with
theoretically and empirically derived rules for generating explicit force
field parameters.
In Discover the Extensible Systematic Force Field (ESFF) is such a
rule-based force field.
ESFF was derived using a mixture of DFT calculations on dressed atoms to
obtain polarizabilities, gas-phase and crystal structures. The  training
set included molecules containg each element in the first six periodes
(except the inert gases). Parameters and charges are generated on-the-fly,
based on the configuration, the local environment and the derived rules.
Within OFF you can access the Universal Force Field (UFF) by Rappe and
Goddard. 
Like ESFF it is a rule based force field, the parameters being generated
based on physically realistic rules. UFF has full coverage of the periodic
table.  

For more information, please visit our web site at http://www.msi.com

---
From: "Andruski, Stephen W." <[email-masked]>

I know that the commercial package Alchemy 2000 from Tripos supports
various transition metals.  I don't know how good their force field is
for these elements, but support is there.  Spartan from Wavefunction may
also support transition elements since their PM3(tm) semi-empirical
method supports them, but I'm not sure about their MM methods.

--
From: David Young <[email-masked]>

Molecular mechanics on transition metals is problematic.  It 
turns out not to be as easy to develop a reliable method as is the case 
for organic simulation by molecular mechanics.  

        In the past, many researchers have parameterized a transition
metal for a specific coordination in a specific class of compounds. 

        The force field that is probably best without manual manipulation 
is UFF.  It is designed and sold by MSI.  It is also starting to get 
incorporated into other packages, such as Gaussian 98.  Even with this, I 
would recommend that you test it on a known structure and examine your 
all of your results carefully.

---
From: Eckart Spitzberg <[email-masked]>

I use for my calculations of tungsten-komplexes the program package
gaussian94 from gaussian inc. ( http://www.gaussian.com ), and I 
think, it is very useful.