Thomas Pijper
thomaspijper@hotmail.com
I cannot find any obvious reasons for your optimization not converging. Further tightening of various criteria may help, though I do not know for sure. Perhaps Alex ha any further suggestions.
Kind regards,
Thom
On Thu Feb 12 '15 8:52pm, Alexander Vasyanin wrote
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>Dear Thomas,
>I attached current output here. Unfortunately optimization process still can not reach covergence criteria even using spherical functions and with a little tweak of $MP2GRD group options suggested by Alex. I also removed precalculation and frequent recalculation of hessian, they were too expensive but ineffective.
>Thanks in advance,
>Alexander
>
>
>
>On Tue Feb 10 '15 11:04pm, Thomas Pijper wrote
>----------------------------------------------
>>Dear Alexander,
>>If case Alex' advice doesn't help with convergence, could you post the output of your calculation? That would allow us to have a better look at what the problem is.
>>Enabling/disabling spherical functions will typically result in slightly different computational results. It is strongly recommended to use the type of functions (Cartesian or spherical) for which the basis was designed.
>>
>>
>>Kind regards,
>>Thom
>>
>>
>>
>>On Tue Feb 10 '15 6:41pm, Alexander Vasyanin wrote
>>--------------------------------------------------
>>>Thank you, Thomas, for reply.
>>>New version of manual is very helpful, I didn't know. I've tried D5 option, but unfortunately it did not solve the problem yet: optimization still "oscilates" around the same geometry with minimal energy changes (less than 1E-6) but with quite large GMAX (not less than 1E-4). I'll wait for tomorrow.
>>>Enabled spherical functions also increased my energy values to about 0.036 Ha. Is it ok?
>>>Thanks in advance,
>>>Alexander
>>>I've tried to use D5 option.
>>>On Mon Feb 9 '15 10:52pm, Thomas Pijper wrote
>>>---------------------------------------------
>>>>Dear Alexander,
>>>>With the aug-cc-pVDZ basis one should enable spherical functions. These are enabled with
>>>>$CONTRL D5=.T. $END
>>>>See pages 68-69 of the manual for more details. Enabling spherical functions may reduce partial linear dependence in your basis and help in getting more accurate MP2 gradients.
>>>>Hope this helps.
>>>>
>>>>
>>>>Kind regards,
>>>>Thom
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>On Mon Feb 9 '15 7:47pm, Alexander Vasyanin wrote
>>>>-------------------------------------------------
>>>>>Dear All,
>>>>>I've got a problem with geometry optimization (see attached input file). DFT methods (B3LYP, PBE0) with the same input geometry converge fine, but MP2 fails to converge showing a progress like this:
>>>>>$ grep 'E=' 1.dat | cat -n
>>>>> 1 E= -727.7926962177 GMAX= 0.0001417 GRMS= 0.0000243
>>>>> 2 E= -727.7926962929 GMAX= 0.0001120 GRMS= 0.0000170
>>>>>I've tried to use symmetry (CS) to make calculation faster with IHREP=5 option, but it also didn't help to reach convergence even after 40 iterations.
>>>>>Is it possible to improve convergence (may be with some option in $MP2GRD)?
>>>>>Thanks in advance!