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-31G
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H4 Ethylene 7 B2g 940 727 -212 1.292
CO2 Carbon dioxide 3 Πu 667 556 -111 1.200
SO2 Sulfur dioxide 1 A1 1151 741 -411 1.554
SO2 Sulfur dioxide 2 A1 518 342 -175 1.513
SO2 Sulfur dioxide 3 B2 1362 718 -644 1.898
NH3 Ammonia 2 torsion A1 950 785 -165 1.211
F2 Fluorine diatomic 1 Σg 894 695 -199 1.287
Cl2 Chlorine diatomic 1 Σg 554 389 -165 1.424
IBr Iodine monobromide 1 Σ 267 203 -64 1.318
ICl Iodine monochloride 1 Σ 381 291 -90 1.310
BF Boron monofluoride 1 Σ 1379 1102 -276 1.251
Na2 Sodium diatomic 1 Σg 158 120 -38 1.313