***, 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 for gradient of singlet state
 CPMCSCF,GRAD,1.1,spin=1,accu=1.0d-7,record=5100.1   !cpmcscf for gradient of triplet state
}

{Force
 SAMC,5101.1                !state averaged gradient for singlet state
 CONICAL,6100.1,NODC}       !save information for OPTCONICAL

{Force
 SAMC,5100.1                !state averaged gradient for triplet state
 CONICAL,6100.1,NODC}       !save information for OPTCONICAL

optg,startcmd=multi,gradient=1.d-6  !find singlet-triplet crossing point