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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 LSDA/6-31G*
Calculated values were scaled by 0.9813.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 182 69 0.621
CH3CONH2 Acetamide 20 A 259 209 -50 1.239
CH3COOH Acetic acid 18 A" 93 68 -25 1.363
CH3OH Methyl alcohol 12 A" 200 350 150 0.571
C2H6O2S Dimethyl sulfone 13 A2 326 264 -62 1.236
C2H6O2S Dimethyl sulfone 20 B1 262 217 -45 1.206
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 314 100 0.682
C2H2 Acetylene 4 Πg 612 473 -139 1.295
CH3NH2 methyl amine 14 A" 1195 941 -254 1.269
CH3COCl Acetyl Chloride 15 A" 166 132 -34 1.260
CBr2F2 Methane, dibromodifluoro- 3 A1 140 329 189 0.425
C2F6 hexafluoroethane 4 A1u 68 29 -39 2.327
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 61 -14 1.233
C3H6O 2-Propen-1-ol 22 A 377 306 -72 1.234
C3H6O 2-Propen-1-ol 24 A 188 119 -69 1.576
C3H6O 2-Propen-1-ol 21 A 554 437 -117 1.268
CH3OCHO methyl formate 18 A" 130 103 -27 1.263
C3H2N2 Malononitrile 6 A1 167 137 -30 1.215
C4H8O Furan, tetrahydro- 33 B 137 58 -79 2.350
C2F4 Tetrafluoroethylene 9 B2u 218 181 -37 1.204
C5H8 Cyclopentene 18 A' 254 165 -89 1.537
C3H3NO Isoxazole 14 A" 1033 848 -185 1.218
C4H4N2 Pyridazine 13 A2 421 337 -84 1.248
C4H6O2 2,3-Butanedione 13 Au 1111 887 -224 1.253
C4H6O2 2,3-Butanedione 21 Bg 240 69 -171 3.460
C4H6O2 2,3-Butanedione 9 Ag 614 508 -106 1.208
C4H6O2 2,3-Butanedione 16 Au 48 26 -22 1.818
C4H2 Diacetylene 8 Πu 630 522 -108 1.206
C5H12 Propane, 2,2-dimethyl- 12 T1 203 323 120 0.628
C2H3NO3 Oxamic acid 16 A" 984 790 -194 1.246
C2H3NO3 Oxamic acid 15 A' 328 257 -71 1.276
C2H3NO3 Oxamic acid 21 A" 162 86 -76 1.875
C2H3NO3 Oxamic acid 3 A' 2600 3420 820 0.760
C3O2 Carbon suboxide 7 Πu 61 139 78 0.437
C5H8 1,4-Pentadiene 31 B 721 590 -131 1.221
C5H8 1,4-Pentadiene 33 B 331 102 -229 3.257
C5H8 1,4-Pentadiene 16 A 137 285 148 0.481
C6H10 1,5-Hexadiene 29 Bg 264 214 -50 1.233
C6H10 1,5-Hexadiene 14 Ag 351 270 -81 1.302
COBr2 Carbonic dibromide 6 B2 512 335 -177 1.531
COBr2 Carbonic dibromide 4 B1 757 509 -248 1.487
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 181 -46 1.255
CH3SSCH3 Disulfide, dimethyl 13 A 117 71 -46 1.644
C3H6O2 1,3-Dioxolane 5 A 1480 2866 1386 0.516
C3H6O2 1,3-Dioxolane 13 A 658 1212 554 0.543
C3H6O2 1,3-Dioxolane 4 A 1509 2893 1384 0.522
C3H6O2 1,3-Dioxolane 6 A 1361 2821 1460 0.482
C2F2 difluoroacetylene 4 Πg 270 166 -104 1.627
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 136 -34 1.252
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 218 74 0.660
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 341 -115 1.338
C5H8 1,3-Pentadiene, (E)- 32 A" 129 215 86 0.600
C5H8 1,3-Pentadiene, (E)- 31 A" 361 260 -101 1.389
CH3 Methyl radical 2 A2" 606 479 -127 1.265
CH2OH Hydroxymethyl radical 9 A 234 444 210 0.527
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 109 -249 3.291
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 879 -257 1.293
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 166 -98 1.590
C4H6 Methylenecyclopropane 17 B1 360 279 -81 1.289
C2Cl2 dichloroacetylene 4 Πg 333 245 -88 1.358
C2Cl2+ dichloroacetylene cation 5 Πu 233 178 -55 1.310
ClFO3 Perchloryl fluoride 6 E 405 334 -71 1.214
BF3+ boron trifluoride cation 3 E' 1662 1224 -438 1.358
BF3+ boron trifluoride cation 4 E' 411 267 -144 1.540
SF4 Sulfur tetrafluoride 4 A1 228 177 -51 1.290
HSO3F Fluorosulfonic acid 11 A 390 324 -66 1.205
BrF5 bromine pentafluoride 6 B2 281 198 -83 1.422
CaF2 Calcium difluoride 2 A1 120 19 -101 6.250
PCl5 Phosphorus pentachloride 2 A1' 370 279 -91 1.325
N2O4 Dinitrogen tetroxide 9 B2u 265 217 -48 1.219
N2O3 Dinitrogen trioxide 9 A" 63 151 88 0.417
C3 carbon trimer 3 Πu 63 138 75 0.458
B2Cl4 Diboron tetrachloride 9 E 104 86 -18 1.209
SiH- silicon monohydride anion 1 Σ 2175 1743 -432 1.248
ZnH2 Zinc hydride 3 Πu 633 490 -142 1.291
ClOO chloroperoxy radical 3 A' 201 316 115 0.637
B2H6 Diborane 14 B2u 368 257 -111 1.434
GeH2 germylene 2 A1 916 1745 829 0.525
GeH2 germylene 1 A1 1856 892 -964 2.081
Mg2 Magnesium diatomic 1 Σg 51 119 68 0.430
ZnCH3 Zinc monomethyl 6 E 315 593 278 0.532