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/SDD
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H4 Ethylene 7 B2g 940 780 -160 1.205
SO2 Sulfur dioxide 1 A1 1151 779 -372 1.478
SO2 Sulfur dioxide 2 A1 518 375 -143 1.381
SO2 Sulfur dioxide 3 B2 1362 831 -531 1.639
NH3 Ammonia 2 torsion A1 950 749 -201 1.269
F2 Fluorine diatomic 1 Σg 894 687 -207 1.301
O2 Oxygen diatomic 1 Σg 1556 1295 -261 1.202
Cl2 Chlorine diatomic 1 Σg 554 402 -152 1.379
IBr Iodine monobromide 1 Σ 267 197 -70 1.354
ICl Iodine monochloride 1 Σ 381 297 -85 1.286
BF Boron monofluoride 1 Σ 1379 1102 -277 1.251