return to home page Computational Chemistry Comparison and Benchmark DataBase Release 18 (October 2016) Standard Reference Database 101 National Institute of Standards and Technology
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Bad vibrational frequency predictions

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 CCSD(T)/cc-pV(T+d)Z
Calculated values were scaled by 0.965.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 294 94 0.681
CH3 Methyl radical 2 A2" 606 480 -127 1.264
NO2 Nitrogen dioxide 1 A1 1318 2600 1282 0.507
NO2 Nitrogen dioxide 2 A1 750 2373 1623 0.316
NO2 Nitrogen dioxide 3 B2 1618 2830 1212 0.572
N2O3 Dinitrogen trioxide 9 A" 63 142 79 0.445
H2POH Phosphinous acid 9 A" 375 262 -113 1.432
Mg2 Magnesium diatomic 1 Σg 51 40 -12 1.292