return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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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 MP2=FULL/CEP-31G
Calculated values were scaled by 0.9427.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H4 Ethylene 7 B2g 940 718 -221 1.308
CO2 Carbon dioxide 3 Πu 667 523 -144 1.275
SO2 Sulfur dioxide 1 A1 1151 897 -254 1.284
SO2 Sulfur dioxide 2 A1 518 366 -152 1.416
NH3 Ammonia 2 torsion A1 950 666 -284 1.427
N2 Nitrogen diatomic 1 Σg 2330 1698 -632 1.372
O2 Oxygen diatomic 1 Σg 1556 981 -576 1.587
Cl2 Chlorine diatomic 1 Σg 554 424 -130 1.307
NO Nitric oxide 1 Σ 1876 4222 2346 0.444
BF Boron monofluoride 1 Σ 1379 1067 -312 1.292