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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)/6-311G**
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH2I2 Diiodomethane 3 A1 704 481 -223 1.464
CH2I2 Diiodomethane 4 A1 285 119 -166 2.396
CH2I2 Diiodomethane 7 B1 896 727 -169 1.233
CH2I2 Diiodomethane 9 B2 738 579 -159 1.275
CH2NN diazomethane 6 B1 406 286 -120 1.419
NH2CN cyanamide 5 torsion A' 408 725 317 0.563
CaF2 Calcium difluoride 2 A1 120 62 -58 1.949
N2O3 Dinitrogen trioxide 9 torsion A" 63 149 86 0.423