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/cc-pVTZ
Calculated values were scaled by 0.901.

Species Name mode Symmetry Experiment Theory difference ratio
C2H3+ vinyl cation 2 A1 2217 2869 652 0.773
C2H4+ Ethylene cation 4 Au 84 426 342 0.197
ClCO carbonyl monochloride 3 A' 335 210 -125 1.593
AlO Aluminum monoxide 1 Σ 979 706 -274 1.388
CH2OH Hydroxymethyl radical 9 A 234 360 126 0.650
CH2OH Hydroxymethyl radical 8 A 482 796 314 0.605
ClOO chloroperoxy radical 1 A' 1443 1079 -364 1.337
ClOO chloroperoxy radical 2 A' 414 730 316 0.567
ClOO chloroperoxy radical 3 A' 201 438 237 0.460
CH3 Methyl radical 2 A2" 606 157 -450 3.868
C2H Ethynyl radical 3 Π 372 676 305 0.550
CHCl2 dichloromethyl radical 4 A' 190 287 97 0.661