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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-31G
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H4 Ethylene 7 B2g 940 723 -217 1.300
SO2 Sulfur dioxide 1 A1 1151 796 -355 1.446
SO2 Sulfur dioxide 2 A1 518 357 -161 1.452
SO2 Sulfur dioxide 3 B2 1362 898 -464 1.517
NH3 Ammonia 2 torsion A1 950 786 -164 1.209
F2 Fluorine diatomic 1 Σg 894 677 -217 1.320
Cl2 Chlorine diatomic 1 Σg 554 386 -169 1.437
BF Boron monofluoride 1 Σ 1379 1116 -262 1.235