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lello
raffaele.borrelli@unito.it

I am trying to perform a SA-MCSCF geometry optimization
of the ground state of a system, and I have the following behaviour
of the energy of the target state:

NSERCH=  0     ENERGY= -915.9734212   RMS GRAD = 0.0095239
 NSERCH=  1     ENERGY= -915.9501045   RMS GRAD = 0.0196205
 NSERCH=  2     ENERGY= -915.9576756   RMS GRAD = 0.0058206
 NSERCH=  3     ENERGY= -915.9634734   RMS GRAD = 0.0091716
 NSERCH=  4     ENERGY= -915.9626773   RMS GRAD = 0.0056877
 NSERCH=  5     ENERGY= -915.9597202   RMS GRAD = 0.0036023
 NSERCH=  6     ENERGY= -915.9586388   RMS GRAD = 0.0022706
 NSERCH=  7     ENERGY= -915.9581777   RMS GRAD = 0.0020863
 NSERCH=  8     ENERGY= -915.9575078   RMS GRAD = 0.0033306
 NSERCH=  9     ENERGY= -915.9566032   RMS GRAD = 0.0036036
 NSERCH= 10     ENERGY= -915.9559209   RMS GRAD = 0.0035010
...
-----
As you can see the first point is quite low in energy but after that
the energy increase a lot. I have let the optimization run for more than 100 cycles but the energy is always high and never reaches
that of the first point.
I have observed this behaviour in a several
cases. Is it just a problem of coordinate choice for the optimization
or am I doing something wrong?
Below is my input:

$CONTRL SCFTYP=MCSCF RUNTYP=OPTIMIZE MAXIT=120
        D5=.T. FSTINT=.T. GENCON=.T. ICHARG=1 MULT=2 INTTYP=HONDO  
        ICUT=11   ITOL=20 $END
$SCF DIRSCF=.TRUE. $END
$SYSTEM TIMLIM=1000000 MEMORY=100000000 KDIAG=0 NOJAC=100 $END
$P2P P2P=.T. DLB=.T. $END
$TRANS MPTRAN=2 DIRTRF=.T. AOINTS=DIST ALTPAR=.T. MODE=112 $END
$BASIS EXTFIL=.T. GBASIS=cc-pVDZ $END
$MCSCF CISTEP=ALDET SOSCF=.T.  NUMFO=6 MAXIT=100 ACURCY=1.0E-7 $END
$MCSCF NTRACK=2 ISTATE=1 $END
$MCSCF NPFLG(9)=1 $END
$DET NCORE=66 NACT=4 NELS=3 NSTATE=4 ITERMX=400
    WSTATE(1)=1.0,1.0 CVGTOL=1.0E-7 $END
$PCM SOLVNT=METHYCL $END
$STATPT NSTEP=200 METHOD=GDIIS OPTTOL=0.0015 NPRT=1 NPUN=2 $END


Thanks in advance,
Lello