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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 MP2/cc-pV(T+d)Z
Calculated values were scaled by 0.9525.

Species Name mode Symmetry Experiment Theory difference ratio
CH3COOH Acetic acid 18 A" 93 73 -20 1.267
CH3OH Methyl alcohol 12 A" 200 295 95 0.679
HCN+ hydrogen cyanide cation 1 Σ 3050 3582 532 0.851
HCN+ hydrogen cyanide cation 2 Σ 1800 2725 925 0.660
CH3COOCH3 methyl acetate 27 A" 110 42 -68 2.613
C3H6O 2-Propen-1-ol 24 A 188 108 -81 1.749
C3H2N2 Malononitrile 6 A1 167 134 -33 1.245
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 A2 193 157 -36 1.228
C5H8 Cyclopentene 18 A' 254 172 -82 1.473
CH2NN diazomethane 6 B1 406 109 -297 3.710
C2H3NO3 Oxamic acid 3 A' 2600 3455 855 0.753
C2H3NO3 Oxamic acid 15 A' 328 258 -70 1.269
C2H3NO3 Oxamic acid 16 A" 984 796 -188 1.237
C2H3NO3 Oxamic acid 17 A" 815 644 -171 1.265
C2H3NO3 Oxamic acid 18 A" 745 606 -139 1.230
C2H3NO3 Oxamic acid 21 A" 162 60 -102 2.687
C5H8 1,4-Pentadiene 16 A 137 289 152 0.474
C5H8 1,4-Pentadiene 17 A 102 83 -19 1.223
CO+ carbon monoxide cation 1 Σ 2214 2737 523 0.809
C4N2 2-Butynedinitrile 3 Σg 692 573 -119 1.208
NaOH sodium hydroxide 3 Π 300 213 -87 1.410
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.679
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 339 -117 1.345
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 123 -48 1.387
CN Cyano radical 1 Σ 2069 2758 689 0.750
C2H Ethynyl radical 2 Σ 1841 2400 559 0.767
C2H Ethynyl radical 3 Π 372 781 409 0.476
CH3OO methylperoxy radical 12 A" 170 123 -47 1.379
CH3 Methyl radical 2 A2" 606 459 -148 1.322
CH2OH Hydroxymethyl radical 9 A 234 419 185 0.559
C4H6 Methylenecyclopropane 17 B1 360 267 -93 1.346
O2+ diatomic oxygen cation 1 Σg 1906 1421 -485 1.342
O3 Ozone 3 B2 1042 2135 1093 0.488
NO Nitric oxide 1 Σ 1904 3184 1280 0.598
NO2 Nitrogen dioxide 3 B2 1618 4022 2404 0.402
N2O4 Dinitrogen tetroxide 9 B2u 265 194 -71 1.367
N2O3 Dinitrogen trioxide 9 A" 63 160 97 0.393
NO3 Nitrogen trioxide 3 E' 1492 2283 791 0.654
NO3 Nitrogen trioxide 4 E' 360 702 342 0.513
C3 carbon trimer 3 Πu 63 164 101 0.386
AlO Aluminum monoxide 1 Σ 979 583 -397 1.681
FO2 Dioxygen monofluoride 1 A' 1487 2684 1197 0.554
FO2 Dioxygen monofluoride 2 A' 579 1247 668 0.464
FO2 Dioxygen monofluoride 3 A' 376 652 276 0.577
H2POH Phosphinous acid 9 A" 375 264 -111 1.421
Mg2 Magnesium diatomic 1 Σg 51 40 -11 1.277