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

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH2I2 Diiodomethane 3 A1 704 511 -193 1.378
CH2I2 Diiodomethane 4 A1 285 126 -159 2.259
CaF2 Calcium difluoride 2 A1 120 48 -72 2.489
NO Nitric oxide 1 Σ 1876 2607 731 0.720