Figure shows the major configurations and their weights for each Ω state in the RASCI (3h, 3e) calculation. The results for RASCI (2h, 2e) are nearly identical to those of RASCI (3h, 3e), with differences in weights of about 0.001; therefore, they are omitted for brevity. This indicates that the dominant configurations for the excited states correspond to single excitations from the HF configuration (the dominant configuration of the ground state). By performing the RASCI (3h, 3e) calculations, two-electron excitation configurations for the excited states are included in the electron correlation, leading to a more balanced estimation of the excitation energies.