Conical intersection opt

TD-DFT

#----------------------------------------------------------------------
# Gradient projection method for CI between T1 and T2 by TDDFT BHHLYP/6-31G
#

$COMPASS 
Title
 C2H4 Molecule test run
Basis
 6-31G
Geometry
C             0.00105315     -0.00093169      1.39922525
C             0.00050809     -0.00028384     -1.39806728
H             0.06224101     -0.93329897      0.85576072
H            -0.06090876      0.99435816      0.98003673
H             0.06239763      0.93551513     -0.85894555
H            -0.06541848     -0.99537328     -0.97815399
END geometry
nosym
skeleton
$END

$bdfopt
iprt
 3
imulti
 2
maxcycle
50
tolgrad
1.d-3
tolene
1.d-6
$end

$xuanyuan
direct
$end

$SCF
RKS
charge
 0
spin
 1
atomorb
DFT
BHHLYP
$END

$tddft
imethod
 1
isf
 1
itda
 1
nexit 
 5
idiag
 1
istore
 1
crit_e
 1.d-8
crit_vec
 1.d-6
lefteig
ialda
 4
$end

$resp
geom
norder
 1
method
 2
iroot
 1 
nfiles
 1
$end

$resp
geom
norder
 1
method
 2
iroot
 2 
nfiles
 1
$end

$resp
iprt
 1
QUAD
FNAC
double
norder
 1
method
 2
nfiles
 1
pairs
 1
 1 1 1 1 1 2
$end

CASSCF

#----------------------------------------------------------------------
# Gradient projection method for CI between S1 and S2 by SA3-CASSCF(4,4)/6-31G
#

$COMPASS 
Title
 C2H4 Molecule test run
Basis
 6-31G
Geometry
C            -0.15706002      0.00190775      0.83652009
C             0.15008784     -0.00133762     -0.83154671
H             0.03427061     -0.96458044      1.25530646
H             0.06498491      0.96390175      1.24999388
H            -0.05275481      0.96366210     -1.24919243
H            -0.03963123     -0.96356671     -1.26123252
END geometry
nosym
$END

$bdfopt
iprt
 3
imulti
 1
tolgrad
1.d-3
tolene
1.d-5
$end

$xuanyuan
$end

$SCF
RHF
charge
 0
spin
 1
atomorb
$END

%cp $BDF_WORKDIR/$BDFTASK.scforb $BDF_WORKDIR/$BDFTASK.inporb

$expandmo
vcmo
occao
2 2
minbas
4
1C|2P-1  
1C|2P0   
2C|2P-1   
2C|2P0   
$end

%cp $BDF_WORKDIR/$BDFTASK.exporb $BDF_WORKDIR/$BDFTASK.inporb

$mcscf
close
6
active
4
actele
4
spin
1
roots
3 3 1
symmetry
1
guess
read
molden
quasi
icas
$end

$grad
nrootgrad                                                                      
2 
double
maxiter
500
mxiter
50
cutcpmc
1.d-5
$end

$grad
nrootgrad                                                                      
3 
double
maxiter
500
mxiter
50
cutcpmc
1.d-5
$end