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XIII.F.2. (III.B.7.b.) (IV.C.7.) (XVIII.B.2.)

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
CH3OH Methyl alcohol 12 A" 200 288 88 0.695
CH3OH Methyl alcohol 12 A" 200 288 88 0.695
COBr2 Carbonic dibromide 4 B1 757 503 -254 1.505
COBr2 Carbonic dibromide 6 B2 512 334 -178 1.532
CH2D2 methane-d2 6 B1 3013 2244 -769 1.343
CH2D2 methane-d2 8 B2 2234 3031 797 0.737
NaOH sodium hydroxide 3 Π 300 166 -134 1.803
C2H Ethynyl radical 3 Π 372 304 -67 1.221
CH2OH Hydroxymethyl radical 9 A 234 396 162 0.591
C2Cl2+ dichloroacetylene cation 5 Πu 233 182 -51 1.279
C2H3+ vinyl cation 2 A1 2217 2901 684 0.764
BF3+ boron trifluoride cation 3 E' 1662 964 -697 1.723
BF3+ boron trifluoride cation 4 E' 411 73 -338 5.638
SiH- silicon monohydride anion 1 Σ 2175 1791 -384 1.215
SiH- silicon monohydride anion 1 Σ 2175 1788 -387 1.216
SiH- silicon monohydride anion 1 Σ 2175 1791 -384 1.215
SiH- silicon monohydride anion 1 Σ 2175 1788 -387 1.216
H3O+ hydronium 2 A1 954 791 -164 1.207
H2POH Phosphinous acid 9 A" 375 254 -121 1.475