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 B3LYP/cc-pVQZ
Calculated values were scaled by 0.9688.

Species Name mode Symmetry Experiment Theory difference ratio
C2H4+ Ethylene cation 4 Au 84 -483 -567 -0.174
CH3OH Methyl alcohol 12 A" 200 287 87 0.697
CHONH2 formamide 12 A" 289 224 -65 1.289
NaOH sodium hydroxide 3 Π 300 129 -171 2.328
H2CS- thioformaldehyde anion 4 B1 450 235 -215 1.917
CH2OH Hydroxymethyl radical 9 A 234 401 167 0.584
C2H3+ vinyl cation 2 A1 2217 2901 684 0.764
HCCN cyanomethylene 5 Π 129 -215 -343 -0.601
C3 carbon trimer 3 Πu 63 95 32 0.665
OPCl Phosphorus oxychloride 2 A' 308 467 159 0.660
OPCl Phosphorus oxychloride 3 A' 492 290 -202 1.695
H2OH2O water dimer 8 A' 103 157 54 0.654
H2POH Phosphinous acid 9 A" 375 257 -118 1.460