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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 CCSD(T)/6-311G*
Calculated values were scaled by 0.9626.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 350 150 0.571
C2H2 Acetylene 4 Πg 612 330 -282 1.857
NaOH sodium hydroxide 3 Π 300 203 -97 1.480
CH3 Methyl radical 2 A2" 606 429 -178 1.414
CH3 Methyl radical 2 A2" 606 429 -178 1.414
CH3 Methyl radical 2 A2" 606 429 -178 1.414
CH3 Methyl radical 2 A2" 606 429 -178 1.414
LiOH lithium hydroxide 3 Π 257 396 139 0.648
CH2OH Hydroxymethyl radical 8 A 482 691 209 0.698
CH2OH Hydroxymethyl radical 9 A 234 458 224 0.511
C2H5 Ethyl radical 9 A' 528 433 -96 1.221
C2H Ethynyl radical 3 Π 372 308 -63 1.205
H2O2 Hydrogen peroxide 4 A 371 307 -64 1.210
F2 Fluorine diatomic 1 Σg 917 742 -174 1.235
AsH3+ Arsine cation 2 A1 452 653 201 0.692
CaF2 Calcium difluoride 2 A1 120 59 -61 2.047
CaOH Calcium monohydroxide 2 Σ 353 632 279 0.558
CaOH Calcium monohydroxide 3 Π 609 365 -244 1.669
Li2O dilithium oxide 3 Πu 112 55 -56 2.016
Mg2 Magnesium diatomic 1 Σg 51 21 -31 2.483
Mg2 Magnesium diatomic 1 Σg 51 21 -31 2.483
Mg2 Magnesium diatomic 1 Σg 51 21 -31 2.483
Mg2 Magnesium diatomic 1 Σg 51 21 -31 2.483
Al2 Aluminum diatomic 1 Σg 286 427 141 0.669
PO Phosphorus monoxide 1 Σ 1233 1924 690 0.641