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 CISD/CEP-121G
Calculated values were scaled by 0.9218.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 395 -217 1.549
SO2 Sulfur dioxide 1 A1 1151 854 -297 1.348
SO2 Sulfur dioxide 2 A1 518 372 -145 1.391
SO2 Sulfur dioxide 3 B2 1362 981 -381 1.389
Cl2 Chlorine diatomic 1 Σg 554 390 -165 1.423
IBr Iodine monobromide 1 Σ 267 193 -74 1.381
ICl Iodine monochloride 1 Σ 381 286 -95 1.331
BF Boron monofluoride 1 Σ 1379 1031 -347 1.337