! EXAM46. ! singles/doubles excited state energies by coupled cluster EOM, ! from an open shell ground state. ! Molecule is NH2, with 43 AOs and 41 MOs in aug-cc-pVDZ basis. ! ! The ground state of NH2 is 2-B-1 arising from a configuration ! with an unpaired electron in a p orbital perpendicular to the ! molecule. We expect a valence state exciting from the in-plane ! lone pair to this singly occupied orbital, of 2-A-1 symmetry. ! In this basis, the next state beyond that lies above 6.5 eV. ! ! reference 2-B-1: FINAL ENERGY= -55.5702884296, in 11 iterations ! reference 2-B-1: CCSD ENERGY= -55.7479225350, in 19 iterations ! excited 1-A-1: EOM-CCSD E= -55.6678983648, in 8 iterations ! so the excitation energy is 2.178 eV. As expected, the 1-A-1 ! state is dominated by the single excition R1(4-->5)= 0.974 ! $contrl scftyp=rohf mult=2 cctyp=eom-ccsd runtyp=energy ispher=1 $end $system mwords=3 $end $basis gbasis=accd $end $guess guess=huckel $end $ccinp ccprp=.false. $end $eominp nstate(1)=1,0,0,0 iroot(1)=1,1 ccprpe=.false. minit=1 noact=3 nuact=5 $end $data NH2...aug-cc-pVDZ basis...excited state @ g.s. MP2 geometry Cnv 2 NITROGEN 7.0 0.0 0.0 -0.0370366120 HYDROGEN 1.0 0.0 -0.8055298238 -0.6814816939 $end