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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/CEP-31G
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
SO2 Sulfur dioxide 1 A1 1151 707 -445 1.629
SO2 Sulfur dioxide 2 A1 518 324 -194 1.597
SO2 Sulfur dioxide 3 B2 1362 180 -1182 7.585
NH3 Ammonia 2 torsion A1 950 745 -205 1.276
H2O Water 1 A1 3657 2431 -1226 1.504
H2O Water 3 B2 3756 2559 -1197 1.468
Cl2 Chlorine diatomic 1 Σg 554 379 -175 1.462
IBr Iodine monobromide 1 Σ 267 195 -72 1.367
ICl Iodine monochloride 1 Σ 381 281 -100 1.357
BF Boron monofluoride 1 Σ 1379 1046 -332 1.318
Na2 Sodium diatomic 1 Σg 158 115 -43 1.376