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 MP3/6-31G
Calculated values were scaled by 0.9659.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 445 -167 1.376
SO2 Sulfur dioxide 1 A1 1151 925 -226 1.244
SO2 Sulfur dioxide 2 A1 518 400 -118 1.295
NH3 Ammonia 2 torsion A1 950 722 -228 1.317
Cl2 Chlorine diatomic 1 Σg 554 410 -145 1.353
NO Nitric oxide 1 Σ 1876 3614 1738 0.519