Subject: standard orientation of point charges

From: "Emadeddin Tajkhorshid" <[email-masked]>
Date: Fri, 2 Aug 1996 09:35:15 -0600

Dear CCLers

I want to study the effect of molecule B on molecule A. The effect of B are
defined as point charges and properties of A will be calculated in the presence
of these charges using G94. Since these points represent a molecular system B,
their position have to be the same as B coordinates relative to A. In G94:

when you define the whole AB molecular system

or

when you define only A as coordinates and B as point charges

you will have different standard orientation for A and it means that the
position of point charges are different in these two. Is there any tool in G94
or other programs to find transformed positions for these charge points?

Thanx in advance

-- 
Emad
*********************************************************************
E. Tajkhorshid				
German Cancer Research Center; DKFZ	Tel: +49 6221 42 2339
Dept. Molecular Biophysics (0810)	FAX: +49 6221 42 2333
P.O.Box 101949				Email: [email-masked]
69009 Heidelberg, FRG
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* It is nice to be important, but it is more important to be nice!   *
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From: Artem Masunov <[email-masked]>
Date: Fri, 02 Aug 1996 15:52:29 -0400 (EDT)

On Fri, 2 Aug 1996  [email-masked] wrote:
> defined as point charges and properties of A will be calculated in the 
> presence of these charges using G94. Since these points represent a
> molecular system B,
> position of point charges are different in these two. Is there any tool in 
> G94 or other programs to find transformed positions for these charge
> points?
> 

Dear Emad,
 You can always get coordinates in the standard orientation by running
short test job (for instance, AM1 instead of RHF). 
 Personally I found much easier to use the cartesian coordinates from
output and keyword NOSYMM, which prevents transformation into standard
orientation. 
 Please note that keyword CHARGE needs input list in AU (rather then in
A).  Of course you can convert, but keyword MASSAGE does the job and
takes cartesians in A. 

Hope it helps,
Artem

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