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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(T)/CEP-121G
Calculated values were scaled by 0.9537.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H4 Ethylene 7 B2g 940 726 -214 1.295
C2H2 Acetylene 4 Πg 612 84 -528 7.262
CO2 Carbon dioxide 3 Πu 667 530 -137 1.259
C3H5 Allyl radical 11 B1 802 586 -216 1.369
SO2 Sulfur dioxide 1 A1 1151 694 -458 1.659
SO2 Sulfur dioxide 2 A1 518 322 -196 1.610
SO2 Sulfur dioxide 3 B2 1362 632 -730 2.156
F2 Fluorine diatomic 1 Σg 894 686 -208 1.303
Cl2 Chlorine diatomic 1 Σg 554 376 -178 1.474
IBr Iodine monobromide 1 Σ 267 193 -74 1.380
ICl Iodine monochloride 1 Σ 381 285 -97 1.340
BF Boron monofluoride 1 Σ 1379 1031 -348 1.337