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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
C3H4O2 β–Propiolactone 21 A" 113 175 62 0.646
CH3CONH2 Acetamide 20 A 259 193 -66 1.342
CH3COOH Acetic acid 18 A" 93 71 -22 1.316
CH3OH Methyl alcohol 12 A" 200 319 119 0.627
CH3COCH3 Acetone 12 A2 77 15 -62 5.206
CH3SOCH3 Dimethyl sulfoxide 12 A' 308 256 -52 1.201
C2H6O2S Dimethyl sulfone 13 A2 326 264 -62 1.235
C2H6O2S Dimethyl sulfone 20 B1 262 193 -69 1.356
C2H6O2S Dimethyl sulfone 19 B1 396 320 -76 1.236
C2H6O2S Dimethyl sulfone 9 A1 294 242 -52 1.216
CH3NH2 methyl amine 14 A" 1195 928 -267 1.288
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 228 -48 1.213
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
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
C3H6O 2-Propen-1-ol 21 A 554 423 -131 1.310
C5H12 Pentane 23 A2 131 105 -26 1.251
C3H2N2 Malononitrile 6 A1 167 137 -30 1.219
C4H8O Furan, tetrahydro- 33 B 137 60 -77 2.269
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 8 A2 919 712 -207 1.291
C5H8 Spiropentane 25 E 308 251 -57 1.228
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 13 Au 1111 923 -188 1.204
C4H6O2 2,3-Butanedione 21 Bg 240 108 -132 2.223
C4H6O2 2,3-Butanedione 9 Ag 614 493 -121 1.245
C6H4 Benzyne 24 B2 472 292 -180 1.617
C5H12 Propane, 2,2-dimethyl- 12 T1 203 299 96 0.680
C2H3NO3 Oxamic acid 16 A" 984 783 -201 1.256
C2H3NO3 Oxamic acid 18 A" 745 595 -150 1.251
C2H3NO3 Oxamic acid 20 A" 315 240 -75 1.314
C2H3NO3 Oxamic acid 15 A' 328 251 -77 1.307
C2H3NO3 Oxamic acid 17 A" 815 637 -178 1.280
C2H3NO3 Oxamic acid 21 A" 162 51 -111 3.167
C2H3NO3 Oxamic acid 3 A' 2600 3465 865 0.750
CH3CCCH3 2-Butyne 16 E" 371 263 -108 1.412
C3H6O Oxetane 23 B2 1228 998 -230 1.230
C3H6O Oxetane 12 A2 986 799 -187 1.234
C3O2 Carbon suboxide 7 Πu 61 182 121 0.335
HCNO fulminic acid 5 Π 224 110 -114 2.043
C6H12 2-Butene, 2,3-dimethyl- 12 Au 182 148 -34 1.234
C6H12 2-Butene, 2,3-dimethyl- 37 B2u 181 321 140 0.563
C5H8 1,4-Pentadiene 31 B 721 589 -132 1.225
C5H8 1,4-Pentadiene 33 B 331 96 -235 3.455
C5H8 1,4-Pentadiene 17 A 102 85 -17 1.201
C5H8 1,4-Pentadiene 16 A 137 286 149 0.478
C6H10 1,5-Hexadiene 29 Bg 264 162 -102 1.632
C6H10 1,5-Hexadiene 14 Ag 351 255 -96 1.377
C3H8O2S (Methylsulphonyl)ethane 32 ?a 324 259 -65 1.251
C3H8O2S (Methylsulphonyl)ethane 29 ?a 491 403 -88 1.218
C3H8O2S (Methylsulphonyl)ethane 33 ?a 257 207 -50 1.240
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 182 -45 1.247
CH3SSCH3 Disulfide, dimethyl 13 A 117 92 -25 1.268
C6H10 2-Hexyne 25 A' 115 85 -30 1.348
C6H10 2-Hexyne 38 A" 392 250 -142 1.566
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)- 31 A" 456 339 -117 1.344
C5H8 1,3-Pentadiene, (E)- 32 A" 129 203 74 0.634
C5H8 1,3-Pentadiene, (E)- 31 A" 361 254 -107 1.420
C2H5 Ethyl radical 9 A' 528 429 -99 1.232
C2H Ethynyl radical 3 Π 372 1500 1129 0.248
C2H+ Ethynyl cation 3 Π 550 1038 488 0.529
CH3 Methyl radical 2 A2" 606 473 -134 1.283
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 110 -248 3.269
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
HCCF Fluoroacetylene 5 Π 367 292 -75 1.255
C6H6 2,4-Hexadiyne 14 E' 353 282 -71 1.251
H2CCCCH2 Butatriene 16 B3g 330 140 -190 2.350
C4H6 Methylenecyclopropane 17 B1 360 277 -83 1.299
C2Cl2 dichloroacetylene 4 Πg 333 242 -91 1.377
C2Cl2+ dichloroacetylene cation 5 Πu 233 182 -51 1.283
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
PCl5 Phosphorus pentachloride 2 A1' 370 262 -108 1.412
PCl5 Phosphorus pentachloride 7 E' 100 78 -22 1.283
N2O4 Dinitrogen tetroxide 9 B2u 265 221 -44 1.201
N2O3 Dinitrogen trioxide 9 A" 63 126 63 0.500
C3 carbon trimer 3 Πu 63 291 228 0.218
C4 Carbon tetramer 4 Πg 323 473 150 0.683
SiH- silicon monohydride anion 1 Σ 2175 1726 -449 1.260
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