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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=FULL/cc-pV(T+d)Z
Calculated values were scaled by 0.9481.

Species Name mode Symmetry Experiment Theory difference ratio
HCN+ hydrogen cyanide cation 1 Σ 3050 3511 461 0.869
HCN+ hydrogen cyanide cation 2 Σ 1800 2699 899 0.667
CH3COOCH3 methyl acetate 27 A" 110 66 -44 1.675
C3H2N2 Malononitrile 6 A1 167 136 -31 1.227
C4H9N Pyrrolidine 36 A" 65 49 -16 1.335
C5H8 Cyclopentene 18 A' 254 179 -75 1.416
CH2NN diazomethane 6 B1 406 227 -179 1.788
C2H3NO3 Oxamic acid 3 A' 2600 3454 854 0.753
C2H3NO3 Oxamic acid 15 A' 328 261 -67 1.259
C2H3NO3 Oxamic acid 16 A" 984 811 -173 1.213
C2H3NO3 Oxamic acid 17 A" 815 651 -164 1.252
C2H3NO3 Oxamic acid 18 A" 745 612 -133 1.217
C2H3NO3 Oxamic acid 21 A" 162 67 -95 2.423
C5H8 1,4-Pentadiene 16 A 137 292 155 0.469
C5H8 1,4-Pentadiene 17 A 102 83 -19 1.223
CO+ carbon monoxide cation 1 Σ 2214 2727 513 0.812
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.679
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 347 -109 1.314
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 140 -31 1.224
CN Cyano radical 1 Σ 2069 2757 689 0.750
C2H Ethynyl radical 2 Σ 1841 2403 562 0.766
C2H Ethynyl radical 3 Π 372 778 407 0.477
CH3OO methylperoxy radical 12 A" 170 122 -48 1.394
O2+ diatomic oxygen cation 1 Σg 1906 1445 -461 1.319
OClO Chlorine dioxide 3 B2 1110 2259 1149 0.491
N2O3 Dinitrogen trioxide 9 A" 63 161 98 0.391
C3 carbon trimer 3 Πu 63 179 115 0.355
AlO Aluminum monoxide 1 Σ 979 399 -581 2.455
SCN thiocyanato radical 1 Σ 1942 2372 430 0.819
ClOO chloroperoxy radical 2 A' 414 1052 639 0.393
ClOO chloroperoxy radical 3 A' 201 475 274 0.424
H2POH Phosphinous acid 9 A" 375 257 -118 1.460