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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 B1B95/6-31G*
Calculated values were scaled by 0.9493.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 170 57 0.663
CH3CONH2 Acetamide 20 A 259 165 -94 1.566
CH3COOH Acetic acid 18 A" 93 76 -17 1.230
CH3OH Methyl alcohol 12 A" 200 330 130 0.606
C2H6O2S Dimethyl sulfone 13 A2 326 267 -59 1.223
C2H6O2S Dimethyl sulfone 20 B1 262 208 -54 1.260
CH3NH2 methyl amine 14 A" 1195 940 -255 1.271
CHONH2 formamide 12 A" 289 135 -154 2.143
CH3COCl Acetyl Chloride 15 A" 166 129 -37 1.282
CBr2F2 Methane, dibromodifluoro- 3 A1 140 323 183 0.433
C2F6 hexafluoroethane 4 A1u 68 41 -27 1.648
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 518 -114 1.219
CHOCH(CH3)CH3 Propanal, 2-methyl- 17 A' 395 324 -71 1.219
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 61 -14 1.225
CH3COOCH3 methyl acetate 26 A" 136 80 -56 1.704
CH3COOCH3 methyl acetate 27 A" 110 49 -61 2.254
C3H6O 2-Propen-1-ol 22 A 377 309 -69 1.223
C3H6O 2-Propen-1-ol 24 A 188 112 -76 1.685
C3H6O 2-Propen-1-ol 21 A 554 427 -127 1.298
C5H12 Pentane 23 A2 131 107 -24 1.222
C3H2N2 Malononitrile 6 A1 167 139 -28 1.205
C4H8O Furan, tetrahydro- 33 B 137 52 -85 2.639
CH3CH2CHO Propanal 24 A" 135 104 -31 1.293
C5H8 Cyclopentene 18 A' 254 149 -105 1.704
C2H4O3 trioxolane124 21 B 193 161 -32 1.201
C4H6O2 2,3-Butanedione 13 Au 1111 914 -197 1.215
C4H6O2 2,3-Butanedione 21 Bg 240 102 -138 2.353
C4H6O2 2,3-Butanedione 9 Ag 614 504 -110 1.217
C6H4 Benzyne 24 B2 472 370 -102 1.276
C5H12 Propane, 2,2-dimethyl- 12 T1 203 295 92 0.688
C2H3NO3 Oxamic acid 16 A" 984 786 -198 1.252
C2H3NO3 Oxamic acid 18 A" 745 614 -131 1.212
C2H3NO3 Oxamic acid 15 A' 328 252 -76 1.303
C2H3NO3 Oxamic acid 17 A" 815 664 -151 1.228
C2H3NO3 Oxamic acid 21 A" 162 70 -92 2.329
C2H3NO3 Oxamic acid 3 A' 2600 3450 850 0.754
C3O2 Carbon suboxide 7 Πu 61 112 51 0.547
C5H8 1,4-Pentadiene 31 B 721 586 -135 1.230
C5H8 1,4-Pentadiene 33 B 331 98 -233 3.361
C5H8 1,4-Pentadiene 16 A 137 282 145 0.486
C6H10 1,5-Hexadiene 29 Bg 264 208 -56 1.268
C6H10 1,5-Hexadiene 14 Ag 351 273 -78 1.284
COBr2 Carbonic dibromide 6 B2 512 334 -178 1.534
COBr2 Carbonic dibromide 4 B1 757 502 -255 1.508
CH3SSCH3 Disulfide, dimethyl 13 A 117 97 -20 1.203
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 138 -32 1.236
CH3C(SCH3)HCH3 Propane, 2-(methylthio)- 37 A 215 176 -39 1.221
CH3OCH2CN Methoxyacetonitrile 15 A' 243 173 -70 1.405
CH3OCH2CN Methoxyacetonitrile 24 A" 113 86 -27 1.310
C5H8 1,3-Pentadiene, (E)- 32 A" 129 203 74 0.634
C5H8 1,3-Pentadiene, (E)- 31 A" 361 248 -113 1.457
C2H5 Ethyl radical 9 A' 528 427 -101 1.238
CH3 Methyl radical 2 A2" 606 401 -206 1.513
CH2OH Hydroxymethyl radical 9 A 234 439 205 0.533
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 98 -260 3.672
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 863 -273 1.316
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 145 -119 1.824
CHOCHCHCH3 2-Butenal 18 A' 230 187 -43 1.230
C4H6 Methylenecyclopropane 17 B1 360 281 -79 1.282
C2Cl2+ dichloroacetylene cation 5 Πu 233 183 -50 1.275
BF3+ boron trifluoride cation 3 E' 1662 939 -723 1.770
BF3+ boron trifluoride cation 4 E' 411 -104 -515 -3.941
SF4 Sulfur tetrafluoride 4 A1 228 187 -41 1.220
AsH3+ Arsine cation 2 A1 452 676 224 0.669
BrF5 bromine pentafluoride 6 B2 281 210 -71 1.339
ZnCN Zinc monocyanide 3 Π 212 68 -144 3.122
PCl5 Phosphorus pentachloride 2 A1' 370 273 -97 1.355
N2O3 Dinitrogen trioxide 9 A" 63 145 82 0.436
C3 carbon trimer 3 Πu 63 141 78 0.450
SiH- silicon monohydride anion 1 Σ 2175 1752 -423 1.241
ZnH2 Zinc hydride 3 Πu 633 491 -142 1.288
GeH2 germylene 2 A1 916 1748 832 0.524
GeH2 germylene 1 A1 1856 901 -955 2.060
ZnCH3 Zinc monomethyl 6 E 315 585 270 0.538