Subject: HELP: Gometry optimisation with ADF

From: Dave Price <[email-masked]>
Date: Fri, 22 Mar 1996 11:17:52 +0000

Dear Comp Chem Listers,
              I am ahving trouble with a geometry optimisation of
a Rhodium complex containing a chelate ring and a pair of functionalised
ethylene molecules.  The problem is that after starting with the
geometry optimised bis-ethylene complex and replacing the ethylenes
with the functionlised equivalents the calculation will not converge on
an energy minimum.  Rather, it reaches a minimum then over shoots, viz- 

5  E-test:  old,new=  -5.85880, -5.85899 hartree Minimum
6  E-test:  old,new=  -5.85899, -5.85884 hartree
7  E-test:  old,new=  -5.85884, -5.85824 hartree
8  E-test:  old,new=  -5.85824, -5.85780 hartree
9  E-test:  old,new=  -5.85780, -5.85727 hartree
10 E-test:  old,new=  -5.85727, -5.85694 hartree
11 E-test:  old,new=  -5.85694, -5.85687 hartree
12 E-test:  old,new=  -5.85687, -5.85671 hartree

I am using ECPs for all atoms except H, double zeta valence orbitals
and GGA rather than LDA.
Any help?

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Dr. David W. Price,       Tel: +44 (0)1734 875123  extn 7415
Department of Chemistry,  Fax: +44 (0)1734 311610
University of Reading,    e-mail: [email-masked]
Whiteknights,             W.W.W.: 
READING                HTTP://www.chem.rdg.ac.uk/g50/mmrg/dave/dave.html
RG6 2AD                                
U.K.

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