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Re^7: Error: Failure to locate stationary point. Too many steps taken..

Siddheshwar Chopra
sidhusai@gmail.com

Dear sir,
I just ran exetyp=check, before running hessian calcs. And i got the message.....scf did not converge....perform more gradient runs.... so is this sufficient to conclude that global minimum is still far??? I mean do i save myself from running hessian calcs. to confirm it?

n Fri Dec 28 '12 1:44am, Alex Granovsky wrote
----------------------------------------------
>Dear Siddheshwar,

>strictly speaking, this statement means that a stationary point was
>located (i.e. the point where gradient is zero). This statement does
>not mean that the stationary point which was located is a minimum.
>To check this, you need to perform Hessian computations as suggested
>by  Luca.

>Kind regards,
>Alex Granovsky
>
>
>On Thu Dec 27 '12 8:49pm, Luca Maidich wrote
>--------------------------------------------
>>Dear Siddheshwar,
>>the only way I know for being sure that you correctly found a stationary point is to run a frequency analysis job. It is a tedious job but it has to be done.
>>Two considerations:
>>a) if you loose too much OPTTOL value your optimization could lead to non-meaningful results;
>>b) are you sure that what you are doing now is NOT more tedious than running optimization+frequency jobs? :)

>>Kind Regards
>>Luca

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