From:	Lin Ping <plin' at \`chemvx.tamu.edu>
Date:	Mon, 05 May 1997 14:02:54 -0500
Subject:	PES Calculation

Hi ,everyone,

Does anyone have any suggestion about the calculation of potential
energy suface in the bond breaking process? I try to break the C-C
single bond in CH2CH-CN with geometry relaxation, I have tries quite
some methods such as UHF, CASSCF etc.. Also I have tried to put two
fragment( Optimized seperately) together and alter the orbital after a
triplet UHF calculation to make a singlet state and then decrease the
distance between the two carbon. In the casscf calculation I have
included 8 electrons and 10 orbitals to make sure to include the C-C
antibonding orbital. but None of this work properly. I think maybe it is
the delocalization make the calculation become difficult. By the way, I
am new in this area, so there are still a lot of things for me to learn.
Can you give me some suggestions or references in such a calculation?

Also, when using 3-21G and LanL2DZ basis set to calculate a *MoH5
radical , it is unable to find a optimizated geometry and the SCF
calculation converged very slowly, especially when doing a DFT
calculation with LanL2DZ.

Thanks in advance.

LIN Ping
plin ( ( at ) ) chemvx.tamu.edu

--
Department of Chemistry           Phone No. : 409-862-9225
Texas A&M University              E-mail :
College Station TX 77843-3255              plin -x- at -x- warbird.chem.tamu.edu
URL: http://http.tamu.edu/~p0l1112/


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