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 CCSD(T)=FULL/3-21G*
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 483 -129 1.267
CO2 Carbon dioxide 3 Πu 667 548 -119 1.217
O2 Oxygen diatomic 1 Σg 1556 1281 -276 1.215
NO Nitric oxide 1 Σ 1876 1430 -446 1.312
Na2 Sodium diatomic 1 Σg 158 125 -33 1.265