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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/6-31G*
Calculated values were scaled by 0.9603.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 177 64 0.639
CH3CONH2 Acetamide 20 A 259 129 -130 2.006
CH3COOH Acetic acid 18 A" 93 76 -17 1.225
CH3OH Methyl alcohol 12 A" 200 331 131 0.605
CH3COCH3 Acetone 12 A2 77 33 -44 2.306
C2H6O2S Dimethyl sulfone 13 A2 326 267 -59 1.219
C2H6O2S Dimethyl sulfone 20 B1 262 206 -56 1.273
CH3NH2 methyl amine 14 A" 1195 950 -245 1.258
CHONH2 formamide 12 A" 289 83 -206 3.487
CH3COCl Acetyl Chloride 15 A" 166 131 -35 1.265
CH3NO2 Methane, nitro- 11 A" 1583 3066 1483 0.516
CBr2F2 Methane, dibromodifluoro- 3 A1 140 312 172 0.448
C2F6 hexafluoroethane 4 A1u 68 45 -23 1.511
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 523 -109 1.209
CH3COOCH3 methyl acetate 27 A" 110 50 -60 2.200
C3H6O 2-Propen-1-ol 21 A 554 431 -124 1.287
C3H6O 2-Propen-1-ol 24 A 188 113 -75 1.668
C4H8O Furan, tetrahydro- 33 B 137 40 -97 3.424
C4H8O2 1,4-Dioxane 19 Au 288 240 -48 1.201
C5H8 Cyclopentene 18 A' 254 134 -120 1.895
C2H3N3 1H-1,2,4-Triazole 18 A" 640 517 -123 1.238
NH2CN cyanamide 5 A' 408 585 177 0.697
C4H6O2 2,3-Butanedione 21 Bg 240 109 -131 2.199
C4H6O2 2,3-Butanedione 9 Ag 614 503 -111 1.220
C6H4 Benzyne 24 B2 472 390 -82 1.211
C5H12 Propane, 2,2-dimethyl- 12 T1 203 299 96 0.679
C2H3NO3 Oxamic acid 21 A" 162 65 -97 2.498
C2H3NO3 Oxamic acid 15 A' 328 259 -69 1.265
C2H3NO3 Oxamic acid 17 A" 815 663 -152 1.230
C2H3NO3 Oxamic acid 16 A" 984 785 -199 1.253
C2H3NO3 Oxamic acid 18 A" 745 615 -130 1.212
C2H3NO3 Oxamic acid 3 A' 2600 3453 853 0.753
C3O2 Carbon suboxide 7 Πu 61 124 63 0.491
C6H12 2-Butene, 2,3-dimethyl- 12 Au 182 150 -32 1.215
C6H12 2-Butene, 2,3-dimethyl- 37 B2u 181 335 154 0.540
C5H8 1,4-Pentadiene 16 A 137 288 151 0.475
C5H8 1,4-Pentadiene 31 B 721 590 -131 1.221
C5H8 1,4-Pentadiene 33 B 331 101 -230 3.289
C6H10 1,5-Hexadiene 29 Bg 264 181 -83 1.459
C6H10 1,5-Hexadiene 14 Ag 351 257 -94 1.367
COBr2 Carbonic dibromide 6 B2 512 324 -188 1.582
COBr2 Carbonic dibromide 4 B1 757 495 -262 1.528
C3H8O2S (Methylsulphonyl)ethane 32 ?a 324 267 -57 1.213
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 187 -40 1.214
CH3SSCH3 Disulfide, dimethyl 13 A 117 95 -22 1.236
C2F2 difluoroacetylene 4 Πg 270 194 -76 1.390
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 141 -29 1.202
C5H8 1,3-Pentadiene, (E)- 32 A" 129 204 75 0.632
C5H8 1,3-Pentadiene, (E)- 31 A" 361 250 -111 1.444
C2H5 Ethyl radical 9 A' 528 439 -89 1.202
CH3 Methyl radical 2 A2" 606 435 -172 1.394
C4H9N Cyclobutylamine 21 A' 174 144 -30 1.209
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 865 -271 1.313
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 150 -114 1.757
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 100 -258 3.568
OH- hydroxide anion 1 Σ 3738 3281 -457 1.139
C4H6 Methylenecyclopropane 17 B1 360 282 -78 1.278
C2Cl2 dichloroacetylene 4 Πg 333 277 -56 1.203
C2Cl2+ dichloroacetylene cation 5 Πu 233 177 -56 1.319
ClFO3 Perchloryl fluoride 6 E 405 332 -73 1.219
BF3+ boron trifluoride cation 3 E' 1662 974 -687 1.706
BF3+ boron trifluoride cation 4 E' 411 118 -293 3.469
SF4 Sulfur tetrafluoride 4 A1 228 181 -47 1.257
AsH3+ Arsine cation 2 A1 452 688 236 0.657
BrF5 bromine pentafluoride 6 B2 281 203 -78 1.385
ZnCN Zinc monocyanide 3 Π 212 49 -163 4.288
PCl5 Phosphorus pentachloride 2 A1' 370 257 -113 1.441
N2O4 Dinitrogen tetroxide 9 B2u 265 220 -45 1.206
C3 carbon trimer 3 Πu 63 179 116 0.353
CaOH Calcium monohydroxide 3 Π 609 329 -280 1.851
CaOH Calcium monohydroxide 2 Σ 353 601 248 0.587
Cu2 Copper dimer 1 Σg 265 387 122 0.684
SiH- silicon monohydride anion 1 Σ 2175 1731 -444 1.256
ZnH2 Zinc hydride 3 Πu 633 499 -133 1.267
ClOO chloroperoxy radical 3 A' 201 122 -80 1.657
ClOO chloroperoxy radical 2 A' 414 300 -114 1.378
Mg2 Magnesium diatomic 1 Σg 51 42 -9 1.203
ZnCH3 Zinc monomethyl 6 E 315 593 278 0.531