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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 PBEPBE/6-31G(2df,p)
Calculated values were scaled by 0.9897.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 181 68 0.625
CH3CONH2 Acetamide 20 A 259 209 -50 1.241
CH3COOH Acetic acid 18 A" 93 58 -35 1.594
CH3OH Methyl alcohol 12 A" 200 322 122 0.620
CH3COCH3 Acetone 12 A2 77 49 -28 1.583
C2H6O2S Dimethyl sulfone 13 A2 326 268 -58 1.217
C2H6O2S Dimethyl sulfone 20 B1 262 200 -62 1.311
C2H2 Acetylene 4 Πg 612 480 -132 1.275
CH3NH2 methyl amine 14 A" 1195 946 -249 1.263
CHONH2 formamide 12 A" 289 124 -164 2.323
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 230 -46 1.201
CH3COCl Acetyl Chloride 15 A" 166 130 -36 1.277
CBr2F2 Methane, dibromodifluoro- 3 A1 140 327 187 0.428
C2F6 hexafluoroethane 4 A1u 68 50 -18 1.358
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 523 -109 1.207
C3H6O 2-Propen-1-ol 22 A 377 309 -68 1.219
C3H6O 2-Propen-1-ol 24 A 188 113 -75 1.659
C3H6O 2-Propen-1-ol 21 A 554 431 -123 1.285
CH3OCHO methyl formate 18 A" 130 93 -37 1.394
C4H8O Furan, tetrahydro- 33 B 137 26 -111 5.210
C4H8O2 1,4-Dioxane 19 Au 288 239 -49 1.205
C5H8 Cyclopentene 18 A' 254 134 -120 1.899
C2H4O3 trioxolane124 21 B 193 154 -39 1.254
C4H4N2 Pyridazine 13 A2 421 343 -78 1.226
NH2CN cyanamide 5 A' 408 590 182 0.692
C4H6O2 2,3-Butanedione 13 Au 1111 896 -215 1.241
C4H6O2 2,3-Butanedione 21 Bg 240 91 -149 2.628
C4H6O2 2,3-Butanedione 9 Ag 614 498 -116 1.232
C6H4 Benzyne 24 B2 472 364 -108 1.298
C5H12 Propane, 2,2-dimethyl- 12 T1 203 305 102 0.666
C2H3NO3 Oxamic acid 16 A" 984 797 -187 1.234
C2H3NO3 Oxamic acid 15 A' 328 254 -74 1.289
C2H3NO3 Oxamic acid 17 A" 815 671 -144 1.214
C2H3NO3 Oxamic acid 21 A" 162 71 -91 2.277
C2H3NO3 Oxamic acid 3 A' 2600 3478 878 0.747
C3H6O Oxetane 23 B2 1228 1011 -217 1.215
C3H6O Oxetane 12 A2 986 803 -183 1.229
C3H6O Oxetane 18 B1 90 42 -48 2.142
C3O2 Carbon suboxide 7 Πu 61 88 27 0.692
Zn(CH3)2 dimethyl zinc 11 E' 134 96 -38 1.395
C5H8 1,4-Pentadiene 31 B 721 591 -130 1.220
C5H8 1,4-Pentadiene 33 B 331 100 -231 3.296
C5H8 1,4-Pentadiene 17 A 102 84 -18 1.209
C5H8 1,4-Pentadiene 16 A 137 284 147 0.482
C6H10 1,5-Hexadiene 29 Bg 264 192 -72 1.378
C6H10 1,5-Hexadiene 14 Ag 351 253 -98 1.387
COBr2 Carbonic dibromide 6 B2 512 337 -175 1.518
COBr2 Carbonic dibromide 4 B1 757 516 -241 1.466
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 184 -43 1.234
CH3ONO Methyl nitrite 15 A" 186 142 -44 1.309
C3H6O2 1,3-Dioxolane 5 A 1480 2891 1411 0.512
C3H6O2 1,3-Dioxolane 4 A 1509 2907 1398 0.519
C3H6O2 1,3-Dioxolane 6 A 1361 2790 1429 0.488
C3H6O2 1,3-Dioxolane 13 A 658 1203 545 0.547
C2F2 difluoroacetylene 4 Πg 270 166 -104 1.631
C3H7N Cyclopropylamine 12 A' 989 817 -172 1.210
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 139 -31 1.221
CH3OCH2CN Methoxyacetonitrile 15 A' 243 175 -68 1.390
CH3OCH2CN Methoxyacetonitrile 24 A" 113 87 -26 1.302
C5H8 1,3-Pentadiene, (E)- 32 A" 129 209 80 0.618
C5H8 1,3-Pentadiene, (E)- 31 A" 361 256 -105 1.409
CH3 Methyl radical 2 A2" 606 468 -138 1.295
CH2OH Hydroxymethyl radical 9 A 234 437 203 0.535
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 105 -253 3.421
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 867 -269 1.311
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 158 -106 1.675
C3H3 Propargyl radical 7 B1 490 408 -82 1.200
C4H6 Methylenecyclopropane 17 B1 360 284 -76 1.269
C2Cl2+ dichloroacetylene cation 5 Πu 233 184 -49 1.265
BF3+ boron trifluoride cation 3 E' 1662 1143 -519 1.454
BF3+ boron trifluoride cation 4 E' 411 260 -151 1.582
BrF5 bromine pentafluoride 6 B2 281 218 -63 1.287
CaF2 Calcium difluoride 2 A1 120 93 -27 1.284
ClF3 Chlorine trifluoride 3 A1 328 271 -57 1.210
ZnCN Zinc monocyanide 3 Π 212 104 -108 2.042
PCl5 Phosphorus pentachloride 2 A1' 370 272 -98 1.360
PCl5 Phosphorus pentachloride 7 E' 100 81 -19 1.234
N2O4 Dinitrogen tetroxide 9 B2u 265 190 -75 1.396
N2O3 Dinitrogen trioxide 9 A" 63 143 80 0.441
C3 carbon trimer 3 Πu 63 97 33 0.655
CaOH Calcium monohydroxide 2 Σ 353 623 270 0.567
CaOH Calcium monohydroxide 3 Π 609 312 -297 1.952
C4 Carbon tetramer 4 Πg 323 196 -127 1.645
Cu2 Copper dimer 1 Σg 265 429 164 0.617
SiH- silicon monohydride anion 1 Σ 2175 1772 -403 1.227
ZnH2 Zinc hydride 3 Πu 633 349 -284 1.813
ClONO2 Chlorine nitrate 7 A' 273 227 -47 1.207
ClOO chloroperoxy radical 3 A' 201 294 92 0.686
B2H6 Diborane 14 B2u 368 300 -68 1.228
GeH2 germylene 2 A1 916 1852 936 0.495
GeH2 germylene 1 A1 1856 913 -943 2.033
Mg2 Magnesium diatomic 1 Σg 51 107 56 0.477
ZnCH3 Zinc monomethyl 6 E 315 575 260 0.548