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