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-121G
Calculated values were scaled by 0.9427.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H4 Ethylene 7 B2g 940 737 -202 1.274
C2H2 Acetylene 4 Πg 612 311 -301 1.970
CO2 Carbon dioxide 3 Πu 667 522 -145 1.279
SO2 Sulfur dioxide 1 A1 1151 889 -262 1.295
SO2 Sulfur dioxide 2 A1 518 365 -153 1.418
NH3 Ammonia 2 torsion A1 950 733 -217 1.296
N2 Nitrogen diatomic 1 Σg 2330 1700 -630 1.371
O2 Oxygen diatomic 1 Σg 1556 988 -568 1.575
Cl2 Chlorine diatomic 1 Σg 554 422 -133 1.314
NO Nitric oxide 1 Σ 1876 4254 2378 0.441
BF Boron monofluoride 1 Σ 1379 1056 -323 1.306