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=FULL/6-31G
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 445 -167 1.377
CO2 Carbon dioxide 3 Πu 667 544 -123 1.227
SO2 Sulfur dioxide 1 A1 1151 863 -289 1.335
SO2 Sulfur dioxide 2 A1 518 387 -131 1.339
SO2 Sulfur dioxide 3 B2 1362 960 -402 1.419
NH3 Ammonia 2 torsion A1 950 769 -181 1.236
H2O Water 1 A1 3657 2440 -1217 1.499
H2O Water 3 B2 3756 2568 -1188 1.463
Cl2 Chlorine diatomic 1 Σg 554 401 -153 1.381