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)=FULL/cc-pCVTZ
Calculated values were scaled by 0.9663.

Species Name mode Symmetry Experiment Theory difference ratio
CH3 Methyl radical 2 A2" 606 486 -120 1.248
HO2 Hydroperoxy radical 1 A' 3436 1100 -2336 3.124
HO2 Hydroperoxy radical 3 A' 1098 3548 2451 0.309