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Bad vibrational frequency predictions

19 02 11 15 45

Calculated frequencies that differ from experiment by more than 400 cm-1 or have a ratio with experiment outside of 0.7 to 1.2 are listed

Calculated vibrational frequencies ("theory" in table) are calculated at CCSD=FULL/3-21G*
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
H2O Water 1 A1 3657 2471 -1186 1.480
H2O Water 3 B2 3756 2655 -1101 1.415
NO Nitric oxide 1 Σ 1876 1487 -389 1.261
Na2 Sodium diatomic 1 Σg 158 125 -33 1.263