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/CEP-121G
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H4 Ethylene 7 B2g 940 761 -179 1.235
C2H2 Acetylene 4 Πg 612 118 -494 5.178
C3H5 Allyl radical 11 B1 802 616 -186 1.301
SO2 Sulfur dioxide 1 A1 1151 757 -395 1.521
SO2 Sulfur dioxide 2 A1 518 348 -169 1.487
SO2 Sulfur dioxide 3 B2 1362 777 -585 1.752
F2 Fluorine diatomic 1 Σg 894 705 -189 1.269
Cl2 Chlorine diatomic 1 Σg 554 394 -161 1.408
IBr Iodine monobromide 1 Σ 267 203 -64 1.318
ICl Iodine monochloride 1 Σ 381 298 -83 1.279
BF Boron monofluoride 1 Σ 1379 1087 -292 1.269