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 MP4/SDD
Calculated values were scaled by 0.9438.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H4 Ethylene 7 B2g 940 738 -201 1.273
CO2 Carbon dioxide 1 Σg 1333 1020 -313 1.307
CO Carbon monoxide 1 Σ 2143 1509 -634 1.420
SO2 Sulfur dioxide 1 A1 1151 832 -320 1.385
SO2 Sulfur dioxide 2 A1 518 360 -158 1.440
NH3 Ammonia 2 torsion A1 950 699 -251 1.359
N2 Nitrogen diatomic 1 Σg 2330 1785 -545 1.305
F2 Fluorine diatomic 1 Σg 894 687 -207 1.302
O2 Oxygen diatomic 1 Σg 1556 1035 -522 1.504
Cl2 Chlorine diatomic 1 Σg 554 394 -161 1.408
IBr Iodine monobromide 1 Σ 267 192 -75 1.390
ICl Iodine monochloride 1 Σ 381 288 -93 1.323
NO Nitric oxide 1 Σ 1876 3319 1443 0.565
BF Boron monofluoride 1 Σ 1379 1023 -356 1.348