Re: about precomplex

From: David Gallagher <dgallagher-: at :-fujitsu.com>
Subject: Re: about precomplex
Date: Wed, 10 Nov 1999 15:18:35 -0800

If you are using MOPAC, first check you have a true transition state by
 running a FORCE calculation which should show one and only one negative
 vibration. Then run the IRC=1 and IRC=-1 calculations to find the reactants
 and products (minima) on either side of the transition state. One of these
 may lead to the precomplex or intermediate that you suspect.
 Regards,
 David Gallagher, Fujitsu CCS.
 At 01:44 PM 11/10/99 -0800, Yunfeng Hu wrote:
 >Hi,everyone
 >Recently I'm doing some ion reaction and dipolar cycloaddition
 >calculation. I found in both cases that the energy of reactants(simple
 >energy sum of each reactant faraway) is larger than that of TS in gas
 >phase. Can someone tell me how to find the precomplex in an unexpensive
 >way?
 >Thanks in advance.
 >
 >Yunfeng
 >
 >
 >