The best agreement with experiment was achieved by XMS-CASPT2 (IPEA) among the four CASPT2 methods. The maximum deviation was 0.092 eV. The improvement with IPEA shift was particularly significant for the n → π * transition. On the other hand, when IPEA shift was not employed, XMS-CASPT2 underestimated the 0-0 transition energy by 0.19-0.25 eV, which was expected given the well-known systematic underestimation. RMS-CASPT2 without IPEA shift underestimated the 0-0 transition energies even more, by roughly 0.15 eV. Use of the IPEA shift did not completely resolve the underestimation, but the deviation with IPEA shift was up to 0.11 eV, and the agreement with experiment was satisfactory, considering the expected accuracy of MRPTs. For this transition energy, the impact of the IPEA shift was 0.24-0.32 eV, and the deviation from experiment was reduced by approximately 0.2 and 0.3 eV for XMS-and RMS-CASPT2, respectively. The deviation of NEVPT2 from experiment was 0.07-0.13 eV. Considering that there are no empirical parameters in the formulation of NEVPT2 (and that it is size-extensive and free from the intruder state problem), NEVPT2 is also a promising and practical MRPT for determining molecular structures and excitation energies.