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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)/6-31+G**
Calculated values were scaled by 0.939.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 368 -244 1.665
CH3 Methyl radical 2 torsion A2" 606 456 -151 1.330
S3 Sulfur trimer 2 A1 281 524 243 0.537
CuF Copper monofluoride 1 Σ 615 1220 605 0.504