Table 6: Vibrational frequencies 𝜔 𝑒 (cm−1) of the lowest states corresponding to the lowest two asymptotes.

Method 3 Π 𝑔 3 Σ + 𝑢 3 Π 𝑢 3 Σ + 𝑔 1 Π 𝑔 1 Σ + 𝑢 1 Π 𝑢 1 Σ + 𝑔

PQ22017392821913612142
PT21917272721913513135
W91T218177diss33220129diss21
P0T215182911223135116146
GP0T216181diss112261067838
CB3LT220189dissdiss232139137150
B3LT211167diss1321512690139
BLT210157diss27207122diss115
B86T222172diss372221311429
LDAT24718985452471608926
[17]a23120023diss25013121158
[17]b22020832diss244121205104
[87]c211169dissdiss21277175112
[88]d192175diss210134178
[89]d175150dissdiss202107166104
exp 2 2 3 ± 5 e 1 6 1 ± 5 f 2 0 . 3 ± 0 . 2 g 1 2 2 ± 1 0 h 1 4 8 ± 6 i

For the acronyms, see Table 5. T,Qas in Table 5. aWith DK-CASPT2. bWith DK-MRACPF. cWith CI. dWith MRCI. eFrom [92]. fFrom [93]. gFrom [85]. hFrom [94]. iFrom [95].