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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)/6-31G**
Calculated values were scaled by 0.9485.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 325 125 0.616
C2H2 Acetylene 4 Πg 612 371 -241 1.652
CH3CCH propyne 9 E 633 505 -128 1.254
CH3CCH propyne 10 E 328 246 -82 1.332
NaOH sodium hydroxide 3 Π 300 120 -180 2.500
CuO Copper Monoxide 1 Σ 640 6346 5706 0.101
C2H5 Ethyl radical 9 A' 528 438 -90 1.207
C2H Ethynyl radical 3 Π 372 277 -95 1.343
CH3 Methyl radical 2 A2" 606 398 -208 1.522
CH3 Methyl radical 2 A2" 606 398 -208 1.522
CH3 Methyl radical 2 A2" 606 398 -208 1.522
CH3 Methyl radical 2 A2" 606 398 -208 1.522
CH2OH Hydroxymethyl radical 8 A 482 710 228 0.679
CH2OH Hydroxymethyl radical 9 A 234 425 191 0.550
C3H3 Propargyl radical 7 B1 490 393 -97 1.248
H2O2 Hydrogen peroxide 4 A 371 307 -64 1.209
AsH3+ Arsine cation 2 A1 452 662 210 0.683
PO Phosphorus monoxide 1 Σ 1233 1006 -228 1.226
Mg2 Magnesium diatomic 1 Σg 51 15 -36 3.365
Mg2 Magnesium diatomic 1 Σg 51 279 228 0.183
Mg2 Magnesium diatomic 1 Σg 51 15 -36 3.365
Mg2 Magnesium diatomic 1 Σg 51 279 228 0.183