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 MP4=FULL/TZVP
Calculated values were scaled by 0.9663.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 87 -525 7.069
C3H5 Allyl radical 11 B1 802 635 -167 1.263
SO2 Sulfur dioxide 1 A1 1151 917 -234 1.255
NO Nitric oxide 1 Σ 1876 3456 1580 0.543