***, HCN <-> NHC Isomerization - Transition State Optimization and Frequencies print,orbitals,civector rcn=1.18 ang rnh=1.40 ang alpha=55 degree basis=vtz geometry={ C N,1,rcn H,2,rnh,1,alpha} closed,4 ! global setting for casscf inactive space hf ! HF-SCF multi ! CASSCF mrci ! MRCI optg,root=2,variable=energd,hessproc=runrs2 !optimize mrci+q transition state !and caspt2 for hessian runrs2={multi;rs2} !procedure definition for caspt2 ---