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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**
Calculated values were scaled by 0.9863.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 178 65 0.634
CH3CONH2 Acetamide 20 A 259 75 -183 3.428
CH3COOH Acetic acid 18 A" 93 63 -30 1.477
CH3OH Methyl alcohol 12 A" 200 335 135 0.596
C2H6O2S Dimethyl sulfone 13 A2 326 261 -65 1.248
C2H6O2S Dimethyl sulfone 20 B1 262 208 -54 1.263
C2H2 Acetylene 4 Πg 612 480 -132 1.275
CH3NH2 methyl amine 14 A" 1195 946 -249 1.264
CHONH2 formamide 12 A" 289 152 -137 1.905
CH3COCl Acetyl Chloride 15 A" 166 126 -40 1.314
CBr2F2 Methane, dibromodifluoro- 3 A1 140 313 173 0.447
C2F6 hexafluoroethane 4 A1u 68 43 -25 1.586
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 522 -110 1.210
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 61 -14 1.232
C3H6O 2-Propen-1-ol 22 A 377 312 -66 1.211
C3H6O 2-Propen-1-ol 24 A 188 114 -74 1.654
C3H6O 2-Propen-1-ol 21 A 554 431 -123 1.285
CH3OCHO methyl formate 18 A" 130 97 -33 1.336
C3H2N2 Malononitrile 6 A1 167 137 -30 1.217
C4H8O Furan, tetrahydro- 33 B 137 27 -110 5.071
C2F4 Tetrafluoroethylene 7 B2g 508 414 -94 1.227
C5H8 Cyclopentene 18 A' 254 140 -114 1.818
C3H3NO Isoxazole 14 A" 1033 849 -184 1.217
C2H4O3 trioxolane124 21 B 193 155 -38 1.245
C4H4N2 Pyridazine 13 A2 421 340 -81 1.236
C4H6O2 2,3-Butanedione 13 Au 1111 899 -212 1.236
C4H6O2 2,3-Butanedione 21 Bg 240 87 -153 2.751
C4H6O2 2,3-Butanedione 9 Ag 614 497 -117 1.235
C5H12 Propane, 2,2-dimethyl- 12 T1 203 312 109 0.652
C2H3NO3 Oxamic acid 16 A" 984 774 -210 1.272
C2H3NO3 Oxamic acid 15 A' 328 256 -72 1.283
C2H3NO3 Oxamic acid 17 A" 815 670 -145 1.216
C2H3NO3 Oxamic acid 21 A" 162 71 -91 2.286
C2H3NO3 Oxamic acid 3 A' 2600 3466 866 0.750
C3O2 Carbon suboxide 7 Πu 61 123 62 0.495
C5H8 1,4-Pentadiene 31 B 721 587 -134 1.229
C5H8 1,4-Pentadiene 33 B 331 100 -231 3.312
C5H8 1,4-Pentadiene 17 A 102 84 -18 1.214
C5H8 1,4-Pentadiene 16 A 137 286 149 0.479
C6H10 1,5-Hexadiene 29 Bg 264 187 -77 1.413
C6H10 1,5-Hexadiene 14 Ag 351 254 -97 1.382
COBr2 Carbonic dibromide 6 B2 512 322 -190 1.589
COBr2 Carbonic dibromide 4 B1 757 496 -261 1.525
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 185 -42 1.228
CH3ONO Methyl nitrite 15 A" 186 136 -50 1.365
C3H6O2 1,3-Dioxolane 5 A 1480 2885 1405 0.513
C3H6O2 1,3-Dioxolane 4 A 1509 2903 1394 0.520
C3H6O2 1,3-Dioxolane 6 A 1361 2846 1485 0.478
C3H6O2 1,3-Dioxolane 13 A 658 1205 547 0.546
C3H7N Cyclopropylamine 12 A' 989 817 -172 1.211
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 140 -30 1.213
GeO2 Germanium dioxide 3 Πu 196 160 -35 1.222
LiOH lithium hydroxide 3 Π 257 205 -51 1.250
C5H8 1,3-Pentadiene, (E)- 32 A" 129 206 77 0.627
C5H8 1,3-Pentadiene, (E)- 31 A" 361 253 -108 1.425
CH3 Methyl radical 2 A2" 606 462 -144 1.311
CH2OH Hydroxymethyl radical 9 A 234 436 202 0.536
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 105 -253 3.421
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 870 -266 1.306
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 157 -107 1.676
SO2F2 Sulfuryl fluoride 4 A1 385 321 -64 1.201
SO2F2 Sulfuryl fluoride 5 A2 388 321 -67 1.210
C4H6 Methylenecyclopropane 17 B1 360 274 -86 1.314
C2Cl2 dichloroacetylene 4 Πg 333 202 -131 1.651
C2Cl2+ dichloroacetylene cation 5 Πu 233 176 -57 1.324
ClFO3 Perchloryl fluoride 3 A1 549 456 -93 1.205
ClFO3 Perchloryl fluoride 5 E 589 490 -99 1.201
ClFO3 Perchloryl fluoride 6 E 405 320 -85 1.266
BF3+ boron trifluoride cation 3 E' 1662 1131 -530 1.469
BF3+ boron trifluoride cation 4 E' 411 269 -142 1.530
SOCl2 thionyl chloride 4 A' 194 158 -36 1.228
SF4 Sulfur tetrafluoride 4 A1 228 171 -57 1.335
AsH3+ Arsine cation 2 A1 452 665 213 0.680
BrF5 bromine pentafluoride 6 B2 281 188 -93 1.491
BrF5 bromine pentafluoride 8 E 415 340 -75 1.219
BrF5 bromine pentafluoride 3 A1 369 304 -65 1.213
ClF3 Chlorine trifluoride 6 B2 442 355 -87 1.244
ClF3 Chlorine trifluoride 3 A1 328 258 -70 1.271
Cl2O Dichlorine monoxide 3 B2 686 551 -135 1.244
SO2Cl2 Sulfuryl chloride 4 A1 218 180 -38 1.209
NCl3 nitrogen trichloride 3 E 642 513 -129 1.251
PCl5 Phosphorus pentachloride 2 A1' 370 259 -111 1.426
PCl5 Phosphorus pentachloride 7 E' 100 82 -18 1.226
N2O4 Dinitrogen tetroxide 9 B2u 265 189 -76 1.403
N2O3 Dinitrogen trioxide 9 A" 63 140 77 0.449
C3 carbon trimer 3 Πu 63 110 46 0.578
CaOH Calcium monohydroxide 2 Σ 353 601 248 0.587
CaOH Calcium monohydroxide 3 Π 609 293 -316 2.079
C4 Carbon tetramer 4 Πg 323 209 -114 1.547
Cu2 Copper dimer 1 Σg 265 411 146 0.644
SiH- silicon monohydride anion 1 Σ 2175 1741 -434 1.249
SF2 sulfur difluoride 2 A1 355 295 -60 1.205
ZnH2 Zinc hydride 3 Πu 633 464 -169 1.364
ClONO2 Chlorine nitrate 7 A' 273 222 -51 1.232
B2H6 Diborane 14 B2u 368 304 -64 1.211
BrOBr Bromine oxide 3 B2 629 523 -106 1.202
GeH2 germylene 2 A1 916 1927 1011 0.475
GeH2 germylene 1 A1 1856 908 -948 2.044
Mg2 Magnesium diatomic 1 Σg 51 103 52 0.497
ZnCH3 Zinc monomethyl 6 E 315 601 286 0.524