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 QCISD/CEP-121G
Calculated values were scaled by 0.9537.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 277 -335 2.211
C3H5 Allyl radical 11 B1 802 609 -192 1.316
SO2 Sulfur dioxide 1 A1 1151 723 -429 1.593
SO2 Sulfur dioxide 2 A1 518 331 -187 1.564
SO2 Sulfur dioxide 3 B2 1362 456 -906 2.989
H2O Water 1 A1 3657 2354 -1303 1.554
H2O Water 3 B2 3756 2479 -1277 1.515
Cl2 Chlorine diatomic 1 Σg 554 385 -169 1.440
IBr Iodine monobromide 1 Σ 267 195 -72 1.367
ICl Iodine monochloride 1 Σ 381 288 -93 1.325
BF Boron monofluoride 1 Σ 1379 1030 -348 1.338