Subject: Transition metals in MOPAC

From: [email-masked] (Pablo Vitoria)
Date: Wed, 15 May 1996 16:06:41 +0000

Hi,

I've used MOPAC 6.0 for some calculations on organic molecules. But now I'd
like to calculate energies and molecular orbitals of large inorganic
molecules containing W, Mo, V or Nb atoms (polyoxoanions).I know these kind
of calculations can be done with EH methods. But I cannot find any
parameters for those heavy atoms for any of the semiempirical methods used
by MOPAC.
Can anybody help pointing to some literature about the subject or
suggesting the use of other programs or methods for that kind of molecules?
 Besides, I'd like to calculate the nteraction of those anions with
aromatic rings, to compare the theoretical results with the crystal
structure of some compounds. Can this be done with MOPAC?

Thank you very much for any help.

Pablo

--------------------------------------------------------------------------------
Pablo Vitoria Garcia
Departamento de Quimica Inorganica, Facultad de Ciencias
Universidad del Pais Vasco (UPV/EHU)
Apartado 644, E-48080 Bilbao
SPAIN
Phone: +34 4 4647700 Ext. 2450
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From: "Wayne Huang" <[email-masked]>
Date: Wed, 15 May 1996 10:43:46 -0700

On May 15,  4:06pm, Pablo Vitoria wrote:
> Subject: CCL:M:Transition metals in MOPAC
> Hi,
>

Hi, Pablo:

Regarding your inquiry about semiempirical methods on transition metals,
Spartan PM3(tm) method can provide the capability for your TM modeling.

This module has been actively under development for three years now, along
with our DFT module, aiming to provide tools for transition metals modeling.
Currently PM3(TM), which includes d-orbitals, has parameters for total of
15 d transition metals (Ti, Cr, Mn, Fe, Co, Ni, Cu, Zr, Mo, Rh, Pd, Hf, Ta
and W) plus Gd from La series.

In addition to PM3(tm), the PM3 module has been added additional parameters.
Boron and Calcium, for the first time, are available in PM3 method.  Moreover,
as some of you are aware, the well-known problem within PM3 model - non-bonded
hydrogen are too attractive - has bee coorected by introducing a repulsive term
between non-bonded hydrogens into the PM3 energy expression. This correction is
a default in PM3(tm) and Option keyword "HHon" in PM3 module.

Hope this helps!

--Wayne

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