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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 MP3/6-311G*
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 447 -165 1.369
CH2I2 Diiodomethane 3 A1 704 496 -208 1.420
CH2I2 Diiodomethane 4 A1 285 122 -163 2.334
CH2I2 Diiodomethane 9 B2 738 604 -134 1.222
NO Nitric oxide 1 Σ 1876 2822 946 0.665
NI3 Nitrogen triiodide 3 E 354 594 240 0.596