return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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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 MP4=FULL/6-311G*
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 337 -275 1.818
CH2I2 Diiodomethane 3 A1 704 479 -225 1.470
CH2I2 Diiodomethane 4 A1 285 118 -167 2.411
CH2I2 Diiodomethane 7 B1 896 737 -159 1.215
CH2I2 Diiodomethane 9 B2 738 577 -161 1.280
IF5 pentafluoroiodine 7 E 591 329 -262 1.797
NO Nitric oxide 1 Σ 1876 3559 1683 0.527