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Re^3: Need help regarding using Symmetry and multiplicity both..

Alex Granovsky
gran@classic.chem.msu.su


Dear Siddheshwar,

the most typical error is incorrectly selected unique atoms.
Please find attached correct input file with symmetry.

Kind regards,
Alex Granovsky


On Tue Feb 25 '14 12:25pm, Siddheshwar Chopra wrote
---------------------------------------------------
>Dear Alex,
>What could be the possible errors you are pointing to? Please find attached an i/p file.

>Regards,

>On Thu Feb 20 '14 1:21am, Alex Granovsky wrote
>----------------------------------------------
>>Dear Siddheshwar,

>>>1) I understand when RHF is used and when ROHF.. Now could anyone clarify:
>>>TO MAKE EVEN NO. OF ELECTRONS (assuming the system has odd no. of electrons) IN SYSTEM, I CAN EITHER ADD +1 OR -1 CHARGE USING icharg... �(FOR RHF)
>>>SECOND WAY I CAN ALSO CHANGE THE MULTIPLICITY OF THE SYSTEM AND RUN ROHF... BUT BY DOING THIS I HAVE ADDED A SPIN TO THE SYSTEM..
>>>Please tell me... Are not both ways same?? Don't both the ways mean that I have added an electron?
>>
>>
>>1) Normally, there should be some physical or chemical ground (a model)
>>behind your QC computations. This model defines what should the
>>appropriate multiplicity and the overall charge be.

>>>2) I was running RHF on of such cluster with C1 symmetry and even no. of electrons. It worked well. But when I added symmetry to the i/p file and added ONLY the symmetry atoms, then I got errors: a) ODD no. of electrons. Cant run RHF �and b) too many primitive bend coordinates. For around 70 atoms in total (with C1)
>>>How should I go about this problem now? I want to use symmetry in my case.

>>2) This means you have made some errors in your input file.

>>Kind regards,
>>Alex Granovsky

>>On Mon Feb 10 '14 2:53pm, Siddheshwar Chopra wrote
>>--------------------------------------------------
>>>Dear Sir,
>>>I am stuck with some doubts and not able to get them clarified at all. They are::

>>>Say I have a CxHyMetal cluster...
>>
>>
>>>Please help.
>>>
>>>
>>>

This message contains the 1 kb attachment
[ SAMPLE_symmetry.inp ]


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