***,H2S diabatic A" states basis=VDZ !use cc-pVDZ basis set symmetry,x,planeyz !use Cs symmetry & fix orientation of the molecule orient,noorient !dont allow automatic reorientation geometry={s;h1,s,r1;h2,s,r2,h1,theta} !Z-matrix geometry input gprint,orbitals,civector !global print options text,reference calculation for C2V theta=92.12,r1=2.3,r2=2.3 !reference geometry {hf;occ,7,2;wf,18,1} !scf calculation for ground state {multi;occ,9,2;closed,4,1; !define active and inactive spaces wf,18,2;state,2; !two A" states (1B1 and 1A2 in C2v) orbital,2140.2} !save orbitals to 2140.2 reforb=2140.2 text,calculations at displaced geometries rd=[2.4,2.5,2.6] !define a range of bond distances do i=1,#rd !loop over displaced geometries r2=rd(i) !set r2 to current distance {multi;occ,9,2;closed,4,1; !same wavefunction definition as at reference geom. wf,18,2;state,2; orbital,2141.2 !save new orbitals to record diab,reforb} !compute diabatic orbitals using reference orbitals !stored on record reforb reforb=2141.2 !set variable reforb to the new orbitals. enddo