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 MP4=FULL/CEP-31G
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H4 Ethylene 7 B2g 940 731 -209 1.286
CO2 Carbon dioxide 1 Σg 1333 1070 -263 1.246
CO2 Carbon dioxide 3 Πu 667 530 -137 1.258
CO Carbon monoxide 1 Σ 2143 1592 -551 1.346
SO2 Sulfur dioxide 1 A1 1151 894 -257 1.287
SO2 Sulfur dioxide 2 A1 518 365 -153 1.420
NH3 Ammonia 2 torsion A1 950 775 -175 1.226
N2 Nitrogen diatomic 1 Σg 2330 1900 -430 1.226
F2 Fluorine diatomic 1 Σg 894 734 -159 1.217
O2 Oxygen diatomic 1 Σg 1556 1221 -335 1.274
Cl2 Chlorine diatomic 1 Σg 554 403 -151 1.375
NO Nitric oxide 1 Σ 1876 3127 1251 0.600
BF Boron monofluoride 1 Σ 1379 1084 -295 1.272
Na2 Sodium diatomic 1 Σg 158 130 -28 1.217