Firefly and PC GAMESS-related discussion club


 
Learn how to ask questions correctly  
 
 
We are NATO-free zone
 



Re^2: Optimization of conical intersection with penalty function method: how to control the gap?

GrEv
grevgen13@gmail.com


Dear Alex,

Thanks very much for your reply.
Just a curios question, what does the SHIFT option do?

Best regards,
Evgeniy

On Sat Oct 22 '16 6:00pm, Alex Granovsky wrote
----------------------------------------------
>Dear Evgeniy,

>there is no direct control over the energy gap for penalty-based CoIn
>optimization procedures. The gap can be controlled indirectly using
>parameters defining a penalty function. The larger is the "strength"
>of penalty function the smaller will be the gap. With Firefly, the
>strength is controlled by the parameter B of $mcaver group.

>Kind regards,
>Alex
>
>
>
>
>
>
>On Sat Oct 22 '16 11:50am, GrEv wrote
>-------------------------------------
>>Hello,

>>I am doing optimization of the minimum energy conical intersection using the penalty function method, with the following input (from the manual, p. 176) :

>>$MCAVER TARGET=MIXED PENLTY=2 XGRAD=.F. $END
>>$STATPT OPTTOL=0.00005 NSTEP=500 method=qa trmax=0.05 dxmax=0.05
>> HSSEND=.f. $END
>>$NUMGRD ORDER=2 DELTA=0.01 ISTATE=1 JSTATE=2 NGRADS=2 PRAXES=1 $END

>>Using this input I found a conical intersection (CoIn), with the final gap between the states of 0.003. I'd like however to have a smaller gap, let's say 0.0001. How this could be done. I've tried to use the SHIFT option in $MCAVER, setting SHIFT=0.0001. It however didn't do the job. I got a CoIn with almost the same gap as before.
>>Many thanks!

>>Evgeniy


[ Previous ] [ Next ] [ Index ]           Sat Oct 22 '16 7:39pm
[ Reply ] [ Edit ] [ Delete ]           This message read 193 times