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 PBEPBEultrafine/6-31G
Calculated values were scaled by 0.9862.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CO2 Carbon dioxide 3 Πu 667 532 -135 1.253
SO2 Sulfur dioxide 1 A1 1151 848 -303 1.358
SO2 Sulfur dioxide 2 A1 518 365 -153 1.418
SO2 Sulfur dioxide 3 B2 1362 942 -420 1.445
NH3 Ammonia 2 torsion A1 950 417 -533 2.280
Cl2 Chlorine diatomic 1 Σg 554 448 -107 1.238