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 B3LYP/aug-cc-pVQZ
Calculated values were scaled by 0.9689.

Species Name mode Symmetry Experiment Theory difference ratio
C2H4+ Ethylene cation 4 Au 84 -486 -570 -0.173
NaOH sodium hydroxide 3 Π 300 166 -134 1.803
CH2OH Hydroxymethyl radical 9 A 234 396 162 0.591
C2H3+ vinyl cation 2 A1 2217 2901 684 0.764
C2H4O4 Formic acid dimer 13 Au 1050 75 -975 14.091
H2POH Phosphinous acid 9 A" 375 254 -121 1.475
CH3BO Borane, methyloxo- 7 E 897 1414 517 0.634