return to home page

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/6-31+G**
Calculated values were scaled by 0.9886.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 179 66 0.632
CH3CONH2 Acetamide 20 A 259 198 -61 1.307
CH3COOH Acetic acid 18 A" 93 53 -40 1.769
CH3OH Methyl alcohol 12 A" 200 317 117 0.630
C2H6O2S Dimethyl sulfone 13 A2 326 267 -59 1.222
C2H6O2S Dimethyl sulfone 20 B1 262 208 -54 1.258
C2H6O2S Dimethyl sulfone 19 B1 396 330 -66 1.202
CH3NH2 methyl amine 14 A" 1195 938 -257 1.274
CH3COCl Acetyl Chloride 15 A" 166 117 -49 1.422
CBr2F2 Methane, dibromodifluoro- 3 A1 140 321 181 0.437
C2F6 hexafluoroethane 4 A1u 68 54 -14 1.257
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 524 -108 1.207
C6H4O2 parabenzoquinone 30 B3u 109 90 -19 1.209
C3H6O 2-Propen-1-ol 24 A 188 112 -76 1.685
C3H6O 2-Propen-1-ol 21 A 554 429 -125 1.291
CH3OCHO methyl formate 18 A" 130 108 -22 1.206
C3H2N2 Malononitrile 6 A1 167 137 -30 1.220
C4H8O Furan, tetrahydro- 33 B 137 36 -101 3.802
C2Cl4 Tetrachloroethylene 4 Au 110 91 -19 1.206
C5H8 Cyclopentene 18 A' 254 147 -107 1.731
C3H3NO Isoxazole 14 A" 1033 850 -183 1.215
C2H4O3 trioxolane124 21 B 193 159 -34 1.218
C4H4N2 Pyridazine 13 A2 421 340 -81 1.240
C4H6O2 2,3-Butanedione 13 Au 1111 901 -210 1.234
C4H6O2 2,3-Butanedione 21 Bg 240 98 -142 2.454
C4H6O2 2,3-Butanedione 9 Ag 614 495 -119 1.241
C5H12 Propane, 2,2-dimethyl- 12 T1 203 313 110 0.649
C2H3NO3 Oxamic acid 16 A" 984 783 -201 1.257
C2H3NO3 Oxamic acid 18 A" 745 614 -131 1.212
C2H3NO3 Oxamic acid 15 A' 328 255 -73 1.288
C2H3NO3 Oxamic acid 17 A" 815 656 -159 1.241
C2H3NO3 Oxamic acid 21 A" 162 66 -96 2.438
C2H3NO3 Oxamic acid 3 A' 2600 3466 866 0.750
C3O2 Carbon suboxide 7 Πu 61 163 102 0.373
C5H8 1,4-Pentadiene 31 B 721 587 -134 1.227
C5H8 1,4-Pentadiene 33 B 331 100 -231 3.303
C5H8 1,4-Pentadiene 16 A 137 289 152 0.474
C6H10 1,5-Hexadiene 29 Bg 264 184 -80 1.436
C6H10 1,5-Hexadiene 14 Ag 351 253 -98 1.385
C6H10 1,5-Hexadiene 20 Au 649 540 -109 1.201
COBr2 Carbonic dibromide 6 B2 512 335 -177 1.529
COBr2 Carbonic dibromide 4 B1 757 516 -241 1.467
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 187 -40 1.216
CH3ONO Methyl nitrite 15 A" 186 147 -39 1.268
C3H6O2 1,3-Dioxolane 5 A 1480 2907 1427 0.509
C3H6O2 1,3-Dioxolane 13 A 658 1211 553 0.543
C3H6O2 1,3-Dioxolane 4 A 1509 2933 1424 0.514
C3H6O2 1,3-Dioxolane 6 A 1361 2828 1467 0.481
C2F2 difluoroacetylene 4 Πg 270 214 -56 1.263
C3H7N Cyclopropylamine 12 A' 989 806 -183 1.227
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 141 -29 1.208
CaO Calcium monoxide 1 Σ 732 605 -127 1.209
C5H8 1,3-Pentadiene, (E)- 32 A" 129 204 75 0.632
C5H8 1,3-Pentadiene, (E)- 31 A" 361 252 -109 1.433
CH2OH Hydroxymethyl radical 9 A 234 417 183 0.562
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 103 -255 3.460
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 869 -267 1.308
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 156 -108 1.693
SO2F2 Sulfuryl fluoride 9 B2 553 460 -93 1.203
SO2F2 Sulfuryl fluoride 4 A1 385 317 -68 1.214
SO2F2 Sulfuryl fluoride 5 A2 388 319 -69 1.215
C4H6 Methylenecyclopropane 17 B1 360 274 -86 1.312
C2Cl2 dichloroacetylene 4 Πg 333 188 -145 1.772
C2Cl2+ dichloroacetylene cation 5 Πu 233 176 -57 1.322
ClFO3 Perchloryl fluoride 3 A1 549 443 -106 1.239
ClFO3 Perchloryl fluoride 5 E 589 483 -106 1.220
ClFO3 Perchloryl fluoride 6 E 405 314 -91 1.290
BF3+ boron trifluoride cation 4 E' 411 262 -149 1.569
BF3+ boron trifluoride cation 3 E' 1662 1116 -545 1.489
SOCl2 thionyl chloride 4 A' 194 156 -38 1.243
SF4 Sulfur tetrafluoride 3 A1 532 431 -101 1.234
SF4 Sulfur tetrafluoride 7 B1 353 284 -69 1.242
SF4 Sulfur tetrafluoride 4 A1 228 177 -51 1.286
AsH3+ Arsine cation 2 A1 452 666 214 0.678
HSO3F Fluorosulfonic acid 8 A 551 459 -92 1.201
HSO3F Fluorosulfonic acid 11 A 390 321 -69 1.214
BrF5 bromine pentafluoride 6 B2 281 177 -104 1.590
BrF5 bromine pentafluoride 8 E 415 332 -83 1.248
BrF5 bromine pentafluoride 3 A1 369 281 -88 1.312
ClF3 Chlorine trifluoride 6 B2 442 342 -100 1.294
ClF3 Chlorine trifluoride 3 A1 328 238 -90 1.376
Cl2O Dichlorine monoxide 3 B2 686 547 -139 1.254
SO2Cl2 Sulfuryl chloride 4 A1 218 180 -38 1.210
NCl3 nitrogen trichloride 3 E 642 515 -127 1.247
PCl5 Phosphorus pentachloride 2 A1' 370 256 -114 1.445
PCl5 Phosphorus pentachloride 7 E' 100 82 -18 1.226
N2O4 Dinitrogen tetroxide 9 B2u 265 185 -80 1.430
N2O3 Dinitrogen trioxide 9 A" 63 129 66 0.489
Li2O dilithium oxide 3 Πu 112 88 -23 1.264
C3 carbon trimer 3 Πu 63 119 56 0.531
CaOH Calcium monohydroxide 2 Σ 353 562 209 0.628
CaOH Calcium monohydroxide 3 Π 609 368 -241 1.654
C4 Carbon tetramer 4 Πg 323 241 -82 1.342
SiH- silicon monohydride anion 1 Σ 2175 1763 -412 1.234
H3O+ hydronium 2 A1 954 794 -160 1.202
ClONO2 Chlorine nitrate 7 A' 273 217 -56 1.258
GeH2 germylene 2 A1 916 1924 1008 0.476
GeH2 germylene 1 A1 1856 909 -947 2.042
H2OH2O water dimer 8 A' 103 170 67 0.607
H2OH2O water dimer 11 A" 108 177 69 0.611
H2OH2O water dimer 7 A' 143 208 65 0.688
H2OH2O water dimer 12 A" 88 141 53 0.623
Mg2 Magnesium diatomic 1 Σg 51 103 52 0.498
ClS2 Sulfur chloride 2 A' 450 374 -76 1.204
ZnCH3 Zinc monomethyl 6 E 315 588 273 0.536