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)/LANL2DZ
Calculated values were scaled by 0.9431.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H4 Ethylene 7 B2g 940 737 -202 1.274
SO2 Sulfur dioxide 1 A1 1151 722 -429 1.595
SO2 Sulfur dioxide 2 A1 518 339 -178 1.525
SO2 Sulfur dioxide 3 B2 1362 733 -629 1.858
NH3 Ammonia 2 torsion A1 950 704 -246 1.349
F2 Fluorine diatomic 1 Σg 894 646 -248 1.383
O2 Oxygen diatomic 1 Σg 1556 1221 -335 1.274
Cl2 Chlorine diatomic 1 Σg 554 367 -187 1.509
IBr Iodine monobromide 1 Σ 267 184 -83 1.448
ICl Iodine monochloride 1 Σ 381 273 -108 1.394
BF Boron monofluoride 1 Σ 1379 1040 -338 1.325