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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 QCISD(T)/6-311G*
Calculated values were scaled by 0.9628.

Species Name mode Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 326 -286 1.878
CH3OH Methyl alcohol 12 A" 200 350 150 0.571
LiOH lithium hydroxide 3 Π 257 395 139 0.649
NaOH sodium hydroxide 3 Π 300 227 -73 1.324
CH3 Methyl radical 2 A2" 606 428 -178 1.416
CH3 Methyl radical 2 A2" 606 428 -178 1.416
CH3 Methyl radical 2 A2" 606 428 -178 1.416
CH3 Methyl radical 2 A2" 606 428 -178 1.416
CH2OH Hydroxymethyl radical 8 A 482 694 212 0.694
CH2OH Hydroxymethyl radical 9 A 234 459 225 0.510
CH3CO Acetyl radical 3 A' 1875 2860 985 0.656
C2H5 Ethyl radical 9 A' 528 436 -92 1.211
H2O2 Hydrogen peroxide 4 A 371 305 -66 1.215
F2 Fluorine diatomic 1 Σg 917 748 -169 1.226
AsH3+ Arsine cation 2 A1 452 653 201 0.692
CaF2 Calcium difluoride 2 A1 120 59 -61 2.024
CaOH Calcium monohydroxide 2 Σ 353 633 280 0.558
CaOH Calcium monohydroxide 3 Π 609 359 -250 1.697
Li2O dilithium oxide 3 Πu 112 56 -56 2.006
Mg2 Magnesium diatomic 1 Σg 51 20 -31 2.496
Mg2 Magnesium diatomic 1 Σg 51 20 -31 2.496
Al2 Aluminum diatomic 1 Σg 286 421 135 0.679