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Alex Granovsky
gran@classic.chem.msu.su

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On Thu Aug 11 '11 3:42pm, Eldar Mamin wrote
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>i succeeded by this approach(casscf(14,11)/6-31+G**
>geometry and then MRMP2(14,11)/aug-cc-pvdz in o3+c2h3cl calculation.
>Activation energies were resonable.12 electons of ozone ( 6 1s-electons excluded) and 2 electrons of double bond.

>in literature (10.1021/jp025562e
>10.1021/jp0633188 )the smaller active
>space was used (12,9),(10,10).
>
>So do so in o3+dichloretylene calculation.

>But my calculation is not consistent with yours in attached file
>(however i started from geometry i had recieved in analogous 14,11/aug-cc-pvdz run, both in attached). How can i avoid such instability?

>On Wed Aug 10 '11 11:00pm, Alex Granovsky wrote
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>>Hi,

>>see attached.

>>I'm wondering whether the active space used in this calculations is really balanced.

>>Regards,
>>Alex Granovsky

>>On Wed Aug 10 '11 4:39pm, Alex Granovsky wrote
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>>>Hi Eldar,

>>>A couple of additional advises:

>>>1. Use DLCs
>>>2. Increase the overall precision of calculations throughout all stages.

>>>Regards,
>>>Alex Granovsky

>>>On Tue Aug 9 '11 3:01pm, Eldar Mamin wrote
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>>>>On Fri Jul 29 '11 10:31am, Pedro Silva wrote
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>>>>>On Thu Jul 28 '11 3:12pm, Eldar Mamin wrote
>>>>>-------------------------------------------
>>>>>>Dear users of FireFly,

>>>>>>i performed i sadpoint search, and encountered the following
>>>>>>problem: optimization "walk" near the true sadpoint(i know that from calculation of analogous system with one chlor) during most
>>>>>>steps (about 90teps). But suddenly serch "fall" to apparently wrong geometry.

>>>>>>The question is: what can i do for better convergence?

>>>>>In sadpoint cases like this, I have met success by decreasing DXMAX in $STATPT (to 0.05 ou 0.02)

>>>>>>why does FF print $VEC group with only 40 orbitals not 151?

>>>>>By default, the virtual orbitals are only punched in the first and final optimization steps. In all other steps, only the occupied ones are punched. This can be changed with NPUNCH (I think)