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Reply-To: "Kiniu WONG \(Kin-Yiu\)" <kyiwong- at -phy.cuhk.edu.hk>
From: "Kiniu WONG \(Kin-Yiu\)" <kyiwong # - at - # phy.cuhk.edu.hk>
To: <chemistry*- at -*ccl.net>
Subject: Gaussian:  How can I hold initial guess symmetry?
Date: Mon, 19 Mar 2001 02:19:44 +0800
Organization: Physics CUHK
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Dear all,

    From the Gaussian Manual (Gaussian 94 User's Reference P.88-89), we are
able to model an excited state by transposing orbital with Guess=Alter.  And
it recommends use SCF=QC or SCF=DM in order to hold initial guess symmetry
> from one iteration to the next.  But I found that even using these two
keywords, the initial symmetry is not able to be held for some molecules.
So my question is:

Are there any methods such that we are able to hold the initial guess
symmetry with 100% certainty?

    I am a new to the computational chemistry.  Any kinds of suggestions are
useful.  Thank you very much in advance.

Wishes,
Kiniu

----
Kiniu WONG (Kin-Yiu)
Undergraduate student
Department of Physics
The Chinese University of Hong Kong
Email: kiniu ^%at%^ cuhk.edu.hk  or  kyiwong ^%at%^ phy.cuhk.edu.hk