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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)/LANL2DZ
Calculated values were scaled by 0.9537.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H4 Ethylene 7 B2g 940 746 -194 1.260
SO2 Sulfur dioxide 1 A1 1151 708 -444 1.627
SO2 Sulfur dioxide 2 A1 518 334 -184 1.552
SO2 Sulfur dioxide 3 B2 1362 682 -680 1.998
NH3 Ammonia 2 torsion A1 950 712 -238 1.335
F2 Fluorine diatomic 1 Σg 894 668 -226 1.338
O2 Oxygen diatomic 1 Σg 1556 1227 -329 1.268
Cl2 Chlorine diatomic 1 Σg 554 372 -182 1.490
IBr Iodine monobromide 1 Σ 267 187 -80 1.430
ICl Iodine monochloride 1 Σ 381 277 -104 1.376
BF Boron monofluoride 1 Σ 1379 1046 -333 1.318