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
$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.