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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)/6-31G**
Calculated values were scaled by 0.9373.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 362 -250 1.690
CH3 Methyl radical 2 torsion A2" 606 393 -213 1.542
CuCl Copper monochloride 1 Σ 414 818 404 0.506
S3 Sulfur trimer 2 A1 281 526 245 0.534
CuF Copper monofluoride 1 Σ 615 1169 555 0.526