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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 QCISD(TQ)/CEP-121G
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H4 Ethylene 7 B2g 940 757 -183 1.241
C2H2 Acetylene 4 Πg 612 84 -528 7.295
C3H5 Allyl radical 11 B1 802 610 -191 1.314
SO2 Sulfur dioxide 1 A1 1151 811 -340 1.419
SO2 Sulfur dioxide 2 A1 518 362 -156 1.431
SO2 Sulfur dioxide 3 B2 1362 917 -444 1.484
F2 Fluorine diatomic 1 Σg 894 692 -202 1.293
Cl2 Chlorine diatomic 1 Σg 554 390 -165 1.422
NO Nitric oxide 1 Σ 1876 1533 -343 1.224
BF Boron monofluoride 1 Σ 1379 1099 -279 1.254