Excited and ionized states of the ozone molecule with full triples coupled cluster methods.
The role of connected triple excitations in coupled cluster (CC) calculations of vertical excitation energies, ionization potentials, and the electron affinity of the ozone molecule is evaluated. The equation of motion (EOM) and Fock space (FS) multireference CC approaches with full triples have been used in the calculations. The effect of the T(3) and R(3) operators significantly improve the EOM CCSD results for all considered quantities. A similar behavior is observed in the case of the FS-CC calculations. The FS-CC calculations with full triples have been obtained only for the intermediate Hamiltonian realization of the FS approach as the standard formulation diverges. The latter results are rigorously linked, and less expensive since smaller matrices are diagonalized.
Musiał
Monika
M
Institute of Chemistry, University of Silesia, Szkolna 9, 40-006 Katowice, Poland. musial@qtp.ufl.edu
Kucharski
Stanisław A
SA
Zerzucha
Piotr
P
Kuś
Tomasz
T
Bartlett
Rodney J
RJ