return to home page Computational Chemistry Comparison and Benchmark DataBase Release 18 (October 2016) 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/6-31+G**
Calculated values were scaled by 0.8559.

Species Name mode Symmetry Experiment Theory difference ratio
C2H4+ Ethylene cation 4 Au 84 395 311 0.213
C2H Ethynyl radical 3 Π 372 633 261 0.587
CH3 Methyl radical 2 A2" 606 193 -413 3.139
CH2OH Hydroxymethyl radical 8 A 482 767 285 0.628
CH2OH Hydroxymethyl radical 9 A 234 347 113 0.674
C2H3+ vinyl cation 2 A1 2217 2754 537 0.805
CHCl2 dichloromethyl radical 4 A' 190 279 89 0.682
S3- Sulfur trimer anion 3 B2 594 423 -171 1.403
AlO Aluminum monoxide 1 Σ 979 653 -326 1.499
ClOO chloroperoxy radical 1 A' 1443 1026 -417 1.407
ClOO chloroperoxy radical 2 A' 414 686 273 0.603
ClOO chloroperoxy radical 3 A' 201 411 210 0.490
ZnCH3 Zinc monomethyl 6 E 315 548 233 0.575
HSO3 HOSO2 4 A 1097 778 -319 1.410