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/6-31G
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 352 -260 1.740
CO2 Carbon dioxide 1 Σg 1333 1109 -224 1.202
CO2 Carbon dioxide 3 Πu 667 502 -165 1.330
CO Carbon monoxide 1 Σ 2143 1678 -465 1.277
SO2 Sulfur dioxide 1 A1 1151 914 -237 1.259
SO2 Sulfur dioxide 2 A1 518 386 -132 1.341
NH3 Ammonia 2 torsion A1 950 771 -179 1.232
O2 Oxygen diatomic 1 Σg 1556 1049 -507 1.484
Cl2 Chlorine diatomic 1 Σg 554 405 -149 1.369
NO Nitric oxide 1 Σ 1876 3773 1897 0.497