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/6-31G
Calculated values were scaled by 0.9431.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 419 -193 1.460
CO2 Carbon dioxide 3 Πu 667 512 -155 1.302
HO2 Hydroperoxy radical 3 A' 1098 768 -330 1.429
SO2 Sulfur dioxide 1 A1 1151 813 -338 1.416
SO2 Sulfur dioxide 2 A1 518 364 -153 1.421
SO2 Sulfur dioxide 3 B2 1362 904 -458 1.507
NH3 Ammonia 2 torsion A1 950 726 -224 1.308
H2O Water 1 A1 3657 2301 -1356 1.589
H2O Water 3 B2 3756 2422 -1334 1.551
Cl2 Chlorine diatomic 1 Σg 554 378 -176 1.466