[ghemical-devel] Re: RM1 parameterization in MOPAC?

[Rzepa, Henry]

At 20:11 -0400 11/8/06, Geoffrey Hutchison wrote:
>I recently ran across an article on the new "RM1" semiempirical 
>model. Basically, a group from Brazil found a better 
>parameterization for AM1 -- same model, same number of parameters. 
>Just the parameters changed. The result is generally better, except 
>slightly worse on bond and dihedral angles than AM1. But heat of 
>formation, dipole moment, ionization potential (i.e., HOMO energy) 
>and bond lengths are all better.
>
>RMI: A reparameterization of AM1 for H, C, N, O, P, S, F, Cl, Br, and I
>by Rocha GB, Freire RO, Simas AM, et al.
>http://dx.doi.org/10.1002/jcc.20425


there are in fact lots of reparametrisations, most of them hardly 
tested in a general
sense.  I personally would not bother to implement them.
-- 

Henry Rzepa.
+44 (020) 7594 5774 (Voice); +44 (0870) 132 3747 (eFax); 
rzepahs at mac.com (iChat)
  http://www.ch.ic.ac.uk/rzepa/ Dept. Chemistry, Imperial College 
London, SW7  2AZ, UK.

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