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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 B3LYP/CEP-31G*
Calculated values were scaled by 0.9657.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 319 119 0.627
CH3OH Methyl alcohol 12 A" 200 319 119 0.627
CH3OH Methyl alcohol 12 A" 200 319 119 0.627
CH3OH Methyl alcohol 12 A" 200 319 119 0.627
CH3COOH Acetic acid 18 A" 93 71 -22 1.316
C3H4O2 β–Propiolactone 21 A" 113 175 62 0.646
C2H6O2S Dimethyl sulfone 13 A2 326 264 -62 1.235
C2H6O2S Dimethyl sulfone 19 B1 396 320 -76 1.236
C2H6O2S Dimethyl sulfone 20 B1 262 193 -69 1.356
CH3COCH3 Acetone 12 A2 77 15 -62 5.206
CH3CONH2 Acetamide 20 A 259 193 -66 1.342
CH3SOCH3 Dimethyl sulfoxide 12 A' 308 256 -52 1.201
C2H6O2S Dimethyl sulfone 9 A1 294 242 -52 1.216
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 228 -48 1.213
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 228 -48 1.211
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 228 -48 1.213
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 228 -48 1.211
CH3COCl Acetyl Chloride 15 A" 166 136 -30 1.221
CH3NO2 Methane, nitro- 11 A" 1583 3073 1490 0.515
C2F6 hexafluoroethane 4 A1u 68 56 -12 1.212
C3F8 perfluoropropane 13 A2 276 211 -65 1.306
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 512 -120 1.235
CH3COOCH3 methyl acetate 27 A" 110 43 -67 2.584
C3H6O 2-Propen-1-ol 24 A 188 109 -80 1.733
C5H12 Pentane 23 A2 131 105 -26 1.251
C3H2N2 Malononitrile 6 A1 167 137 -30 1.219
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 A2 193 161 -32 1.200
C4H8O2 1,4-Dioxane 19 Au 288 233 -55 1.237
C5H8 Cyclopentene 18 A' 254 178 -76 1.428
C5H8 Spiropentane 25 E 308 251 -57 1.228
C5H8 Spiropentane 8 A2 919 712 -207 1.291
C2H3N3 1H-1,2,4-Triazole 18 A" 640 515 -125 1.243
C2H4O3 trioxolane124 21 B 193 153 -40 1.261
NH2CN cyanamide 5 A' 408 625 217 0.653
C4H6O2 2,3-Butanedione 9 Ag 614 493 -121 1.245
C4H6O2 2,3-Butanedione 13 Au 1111 923 -188 1.204
C4H6O2 2,3-Butanedione 21 Bg 240 108 -132 2.223
C3H6O Oxetane 12 A2 986 799 -187 1.234
C3H6O Oxetane 23 B2 1228 998 -230 1.230
C6H4 Benzyne 24 B2 472 292 -180 1.617
CH3CCCH3 2-Butyne 16 E" 371 263 -108 1.412
C5H12 Propane, 2,2-dimethyl- 12 T1 203 299 96 0.680
C2H3NO3 Oxamic acid 3 A' 2600 3465 865 0.750
C2H3NO3 Oxamic acid 15 A' 328 251 -77 1.307
C2H3NO3 Oxamic acid 16 A" 984 783 -201 1.256
C2H3NO3 Oxamic acid 17 A" 815 637 -178 1.280
C2H3NO3 Oxamic acid 18 A" 745 595 -150 1.251
C2H3NO3 Oxamic acid 20 A" 315 240 -75 1.314
C2H3NO3 Oxamic acid 21 A" 162 51 -111 3.167
C3O2 Carbon suboxide 7 Πu 61 182 121 0.335
HCNO fulminic acid 5 Π 224 110 -114 2.043
C6H10 1,5-Hexadiene 29 Bg 264 162 -102 1.632
C5H8 1,4-Pentadiene 16 A 137 286 149 0.478
C5H8 1,4-Pentadiene 17 A 102 85 -17 1.201
C6H10 1,5-Hexadiene 14 Ag 351 255 -96 1.377
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 182 -45 1.247
CH3SSCH3 Disulfide, dimethyl 13 A 117 92 -25 1.268
CH2D2 methane-d2 6 B1 3013 2246 -767 1.342
CH2D2 methane-d2 8 B2 2234 3033 799 0.737
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 137 -33 1.241
NaOH sodium hydroxide 3 Π 300 239 -61 1.253
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 211 67 0.684
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 210 66 0.684
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 211 67 0.684
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 210 66 0.684
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 339 -117 1.344
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 339 -117 1.344
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 339 -117 1.344
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 339 -117 1.344
C2H5 Ethyl radical 9 A' 528 429 -99 1.232
CH3OO methylperoxy radical 12 A" 170 132 -38 1.284
C2H+ Ethynyl cation 3 Π 550 1038 488 0.529
C2H Ethynyl radical 3 Π 372 1500 1129 0.248
CH2OH Hydroxymethyl radical 9 A 234 411 177 0.569
CH3 Methyl radical 2 A2" 606 473 -134 1.283
CH3 Methyl radical 2 A2" 606 473 -134 1.283
CH3 Methyl radical 2 A2" 606 473 -134 1.283
CH3 Methyl radical 2 A2" 606 473 -134 1.283
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 858 -278 1.324
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 166 -98 1.594
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 110 -248 3.269
H2CCCCH2 Butatriene 16 B3g 330 140 -190 2.350
HCCF Fluoroacetylene 5 Π 367 292 -75 1.255
C4H6 Methylenecyclopropane 17 B1 360 277 -83 1.299
ClFO3 Perchloryl fluoride 3 A1 549 442 -107 1.241
ClFO3 Perchloryl fluoride 5 E 589 476 -113 1.238
ClFO3 Perchloryl fluoride 6 E 405 324 -81 1.252
BF3+ boron trifluoride cation 3 E' 1662 935 -726 1.776
BF3+ boron trifluoride cation 4 E' 411 -102 -513 -4.041
C2Cl2 dichloroacetylene 4 Πg 333 242 -91 1.377
C2Cl2+ dichloroacetylene cation 5 Πu 233 182 -51 1.283
HClO4 perchloric acid 6 A' 569 468 -101 1.215
HClO4 perchloric acid 7 A' 548 451 -97 1.216
HClO4 perchloric acid 8 A' 405 336 -69 1.206
HClO4 perchloric acid 10 A" 576 472 -104 1.219
C3 carbon trimer 3 Πu 63 291 228 0.218
C3 carbon trimer 3 Πu 63 291 228 0.218
C3 carbon trimer 3 Πu 63 291 228 0.218
C3 carbon trimer 3 Πu 63 291 228 0.218
C4 Carbon tetramer 4 Πg 323 473 150 0.683
PCl5 Phosphorus pentachloride 2 A1' 370 262 -108 1.412
PCl5 Phosphorus pentachloride 7 E' 100 78 -22 1.283
N2O3 Dinitrogen trioxide 9 A" 63 126 63 0.500
N2O4 Dinitrogen tetroxide 9 B2u 265 221 -44 1.201
SiH- silicon monohydride anion 1 Σ 2175 1726 -449 1.260
SiH- silicon monohydride anion 1 Σ 2175 1725 -450 1.261
SiH- silicon monohydride anion 1 Σ 2175 1726 -449 1.260
SiH- silicon monohydride anion 1 Σ 2175 1725 -450 1.261
SF5Cl sulfur chloropentafluoride 5 B1 625 439 -186 1.424
SF5Cl sulfur chloropentafluoride 7 B2 505 297 -208 1.698
SF5Cl sulfur chloropentafluoride 11 E 397 234 -163 1.698
H3O+ hydronium 2 A1 954 794 -161 1.202
ClOO chloroperoxy radical 2 A' 414 259 -155 1.598
ClOO chloroperoxy radical 3 A' 201 102 -99 1.973
H2OH2O water dimer 8 A' 103 158 55 0.653
H2OH2O water dimer 12 A" 88 140 52 0.630
H2POH Phosphinous acid 9 A" 375 251 -124 1.493
Cl3- trichloride anion 2 Σu 327 264 -63 1.240