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/CEP-121G
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H4 Ethylene 7 B2g 940 761 -179 1.235
C2H2 Acetylene 4 Πg 612 94 -518 6.496
CO2 Carbon dioxide 1 Σg 1333 1066 -267 1.251
CO2 Carbon dioxide 3 Πu 667 528 -139 1.263
CO Carbon monoxide 1 Σ 2143 1586 -557 1.351
C3H5 Allyl radical 11 B1 802 668 -134 1.201
SO2 Sulfur dioxide 1 A1 1151 892 -259 1.291
SO2 Sulfur dioxide 2 A1 518 367 -151 1.412
N2 Nitrogen diatomic 1 Σg 2330 1853 -477 1.258
F2 Fluorine diatomic 1 Σg 894 742 -151 1.204
O2 Oxygen diatomic 1 Σg 1556 1184 -372 1.315
Cl2 Chlorine diatomic 1 Σg 554 408 -146 1.358
NO Nitric oxide 1 Σ 1876 3339 1463 0.562
BF Boron monofluoride 1 Σ 1379 1069 -309 1.289