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/3-21G*
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 476 -136 1.286
CO2 Carbon dioxide 3 Πu 667 533 -134 1.251
CO Carbon monoxide 1 Σ 2143 1707 -436 1.255
SO2 Sulfur dioxide 1 A1 1151 877 -275 1.314
SO2 Sulfur dioxide 3 B2 1362 1133 -228 1.201
N2 Nitrogen diatomic 1 Σg 2330 1925 -405 1.210
O2 Oxygen diatomic 1 Σg 1556 1123 -434 1.386
NO Nitric oxide 1 Σ 1876 3753 1877 0.500
Na2 Sodium diatomic 1 Σg 158 126 -31 1.247