Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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HF vs MP2 Bad vib. Calc. vs exp. 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Bad vibrational frequency predictions

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 M06-2X/CEP-121G
Calculated values were scaled by 1.