return to home page Computational Chemistry Comparison and Benchmark DataBase Release 19 (April 2018) Standard Reference Database 101 National Institute of Standards and Technology
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Bad vibrational frequency predictions

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 ROHF/6-311G**
Calculated values were scaled by 0.9126.

Species Name mode Symmetry Experiment Theory difference ratio
HCCN cyanomethylene 2 Σ 1735 2235 500 0.776
HCCN cyanomethylene 5 Π 129 -878 -1007 -0.147
C2H3+ vinyl cation 2 A1 2217 2910 693 0.762
CH3 Methyl radical 2 A2" 606 343 -264 1.770
C2H Ethynyl radical 3 Π 372 545 173 0.682
O2+ diatomic oxygen cation 1 Σg 1906 2315 409 0.823
H2CS- thioformaldehyde anion 4 B1 450 -293 -743 -1.538
ZnCl Zinc monochloride 1 Σ 391 284 -107 1.375
OClO- Chlorine dioxide anion 1 A1 790 574 -216 1.376
C2H4+ Ethylene cation 4 Au 84 420 336 0.200
CHCl2 dichloromethyl radical 4 A' 190 297 107 0.641
S3- Sulfur trimer anion 3 B2 594 410 -184 1.450
CH2OH Hydroxymethyl radical 9 A 234 379 145 0.617
CH2OH Hydroxymethyl radical 8 A 482 822 340 0.586
ZnCH3 Zinc monomethyl 6 E 315 584 269 0.540
ClSO Sulfur chloride oxide 1 A' 1163 868 -295 1.340
HSO3 HOSO2 4 A 1097 829 -268 1.323