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Re^8: Error: Failure to locate stationary point. Too many steps taken..

Solntsev Pasha
solntsev@univ.kiev.ua


Dear Siddheshwar
Could you provide input file? It is useful to check for hidden mistakes.

Pavel.



On Fri Dec 28 '12 10:03pm, Siddheshwar Chopra wrote
---------------------------------------------------
>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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