Performance of SOPPA-based methods in the calculation of vertical excitation energies and oscillator strengths

TY - JOUR

T1 - Performance of SOPPA-based methods in the calculation of vertical excitation energies and oscillator strengths

AU - Sauer, Stephan P. A.

AU - Pitzner-Frydendahl, Henrik Frank

AU - Buse, Mogens

AU - Jensen, Hans Jørgen Aagaard

AU - Thiel, Walter

PY - 2015/7/18

Y1 - 2015/7/18

N2 - We present two new modifications of the second-order polarization propagator approximation (SOPPA), SOPPA(SCS-MP2) and SOPPA(SOS-MP2), which employ either spin-component-scaled or scaled opposite-spin MP2 correlation coefficients instead of the regular MP2 coefficients. The performance of these two methods, the original SOPPA method as well as SOPPA(CCSD) and RPA(D) in the calculation of vertical electronic excitation energies and oscillator strengths is investigated for a large benchmark set of 28 medium-sized molecules with 139 singlet and 71 triplet excited states. The results are compared with the corresponding CC3 and CASPT2 results from the literature for both the TZVP set and the larger and more diffuse aug-cc-pVTZ basis set. In addition, the results with the aug-cc-pVTZ basis set are compared with the theoretical best estimates for this benchmark set. We find that the original SOPPA method gives overall the smallest mean deviations from the reference values and the most consistent results.

AB - We present two new modifications of the second-order polarization propagator approximation (SOPPA), SOPPA(SCS-MP2) and SOPPA(SOS-MP2), which employ either spin-component-scaled or scaled opposite-spin MP2 correlation coefficients instead of the regular MP2 coefficients. The performance of these two methods, the original SOPPA method as well as SOPPA(CCSD) and RPA(D) in the calculation of vertical electronic excitation energies and oscillator strengths is investigated for a large benchmark set of 28 medium-sized molecules with 139 singlet and 71 triplet excited states. The results are compared with the corresponding CC3 and CASPT2 results from the literature for both the TZVP set and the larger and more diffuse aug-cc-pVTZ basis set. In addition, the results with the aug-cc-pVTZ basis set are compared with the theoretical best estimates for this benchmark set. We find that the original SOPPA method gives overall the smallest mean deviations from the reference values and the most consistent results.

KW - Faculty of Science

KW - electronically excited states

KW - Oscillator strengths

KW - second-order polarization propagator methods

KW - SOPPA

U2 - 10.1080/00268976.2015.1048320

DO - 10.1080/00268976.2015.1048320

M3 - Journal article

SN - 0026-8976

VL - 113

SP - 2026

EP - 2045

JO - Molecular Physics

JF - Molecular Physics

IS - 13-14

ER -