MOLPRO

42 GEOMETRY OPTIMIZATION (OPTG) 320
***, LiH2
basis=sto-3g
symmetry,nosym
geometry={
Li;
H1,Li,r;
H2,Li,r,H1,theta}
r=3.7
theta=160
{hf;wf,4,1,0}
{multi;
occ,7;
wf,4,1,0; !singlet state
wf,4,1,2; !triplet state
CPMCSCF,GRAD,1.1,spin=0,accu=1.0d-7,record=5101.1
CPMCSCF,GRAD,1.1,spin=1,accu=1.0d-7,record=5100.1
}
!cpmcscf for gradient of singlet state
!cpmcscf for gradient of triplet state
{Force
SAMC,5101.1
CONICAL,6100.1,NODC}
{Force
SAMC,5100.1
CONICAL,6100.1,NODC}
!state averaged gradient for singlet state
!save information for OPTCONICAL
!state averaged gradient for triplet state
!save information for OPTCONICAL
optg,startcmd=multi,gradient=1.d-6
!find singlet-triplet crossing point
http://www.molpro.net/info/current/examples/lih2+_S0T0.com
42.3 Using the SLAPAF program for geometry optimization
It is optionally possible to use the SLAPAF program written by Roland Lindh for geometry
optimizations. This is done by prepending the optimization method with ’SL’. The following
methods are supported:
SLRF
SLNR
SLC1
SLC2
Use the rational function approximation;
Use the Newton-Raphson method;
Use the C1-DIIS method;
Use the C2-DIIS method.
When using DIIS methods (SLC1 or SLC2), the DIIS parameters are specified in the same way
as in standard molpro optimizer.
There are some differences when using the SLAPAF program:
1) It is not possible to use Z-matrix coordinates in the optimization.
2) Instead, one can explicitly define internal coordinates to be varied or fixed.
3) Additional constraints can be imposed on the converged geometry in a flexible way.