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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/cc-pVQZ
Calculated values were scaled by 0.9688.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 292 92 0.685
CH3OH Methyl alcohol 12 A" 200 287 87 0.697
CH3OH Methyl alcohol 12 A" 200 292 92 0.685
CH3OH Methyl alcohol 12 A" 200 287 87 0.697
CH2D2 methane-d2 6 B1 3013 2244 -769 1.343
CH2D2 methane-d2 8 B2 2234 3031 797 0.737
COBr2 Carbonic dibromide 4 B1 757 503 -254 1.505
COBr2 Carbonic dibromide 6 B2 512 334 -178 1.535
C2H Ethynyl radical 3 Π 372 306 -66 1.215
CH2OH Hydroxymethyl radical 9 A 234 401 167 0.583
NaOH sodium hydroxide 3 Π 300 129 -171 2.328
C2Cl2+ dichloroacetylene cation 5 Πu 233 183 -50 1.274
BF3+ boron trifluoride cation 3 E' 1662 964 -698 1.724
BF3+ boron trifluoride cation 4 E' 411 72 -339 5.713
C2H3+ vinyl cation 2 A1 2217 2901 684 0.764
AsH3+ Arsine cation 2 A1 452 683 231 0.662
C3 carbon trimer 3 Πu 63 95 32 0.665
SiH- silicon monohydride anion 1 Σ 2175 1770 -405 1.229
SiH- silicon monohydride anion 1 Σ 2175 1770 -405 1.229
SiH- silicon monohydride anion 1 Σ 2175 1770 -405 1.229
SiH- silicon monohydride anion 1 Σ 2175 1770 -405 1.229
H3O+ hydronium 2 A1 954 789 -166 1.210
H2OH2O water dimer 8 A' 103 156 53 0.658
H2POH Phosphinous acid 9 A" 375 257 -118 1.460
Mg2 Magnesium diatomic 1 Σg 51 42 -9 1.210
Mg2 Magnesium diatomic 1 Σg 51 42 -9 1.209
Mg2 Magnesium diatomic 1 Σg 51 42 -9 1.210
Mg2 Magnesium diatomic 1 Σg 51 42 -9 1.209