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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 0.9857.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 178 65 0.635
CH3COOH Acetic acid 18 A" 93 61 -32 1.528
CH3COCH3 Acetone 12 A2 77 32 -45 2.430
C2H6O2S Dimethyl sulfone 13 A2 326 260 -66 1.252
C2H6O2S Dimethyl sulfone 20 B1 262 207 -55 1.264
CH3CONH2 Acetamide 20 A 259 155 -104 1.675
CH3OH Methyl alcohol 12 A" 200 345 145 0.579
CH3OH Methyl alcohol 12 A" 200 343 143 0.583
CH3OH Methyl alcohol 12 A" 200 345 145 0.579
CH3OH Methyl alcohol 12 A" 200 343 143 0.583
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 306 92 0.699
C2H2 Acetylene 4 Πg 612 445 -167 1.375
CHONH2 formamide 12 A" 289 74 -215 3.913
CH3COCl Acetyl Chloride 15 A" 166 127 -39 1.306
CBr2F2 Methane, dibromodifluoro- 3 A1 140 313 173 0.448
C2F6 hexafluoroethane 4 A1u 68 43 -25 1.587
C3F8 perfluoropropane 13 A2 276 205 -71 1.347
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 523 -109 1.208
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 62 -13 1.204
C3H6O 2-Propen-1-ol 22 A 377 313 -65 1.206
C3H6O 2-Propen-1-ol 24 A 188 114 -74 1.645
CH3OCHO methyl formate 18 A" 130 108 -22 1.208
C3H2N2 Malononitrile 6 A1 167 138 -29 1.214
C2F4 Tetrafluoroethylene 7 B2g 508 414 -94 1.228
C5H8 Cyclopentene 18 A' 254 140 -114 1.818
C2H3N3 1H-1,2,4-Triazole 18 A" 640 522 -118 1.227
C4H4N2 Pyridazine 13 A2 421 341 -80 1.234
C2H2N4 sym-tetrazine 18 B3u 254 113 -141 2.253
C2H2N4 sym-tetrazine 5 Au 335 271 -64 1.237
NH2CN cyanamide 5 A' 408 589 181 0.692
C4H6O2 2,3-Butanedione 13 Au 1111 911 -200 1.220
C4H6O2 2,3-Butanedione 21 Bg 240 98 -142 2.438
C4H6O2 2,3-Butanedione 9 Ag 614 497 -117 1.235
C4H2 Diacetylene 8 Πu 630 504 -126 1.250
C3H6O Oxetane 12 A2 986 814 -172 1.212
C3H6O Oxetane 18 B1 90 23 -67 3.856
C3H6O Oxetane 23 B2 1228 1012 -216 1.213
C2H3NO3 Oxamic acid 15 A' 328 254 -74 1.289
C2H3NO3 Oxamic acid 16 A" 984 775 -209 1.269
C2H3NO3 Oxamic acid 17 A" 815 676 -139 1.205
C2H3NO3 Oxamic acid 21 A" 162 68 -94 2.372
C5H12 Propane, 2,2-dimethyl- 12 T1 203 311 108 0.652
C2H3NO3 Oxamic acid 3 A' 2600 3455 855 0.752
C3O2 Carbon suboxide 7 Πu 61 123 62 0.495
C5H8 1,4-Pentadiene 16 A 137 287 150 0.477
C5H8 1,4-Pentadiene 17 A 102 85 -17 1.205
C6H10 1,5-Hexadiene 14 Ag 351 254 -97 1.382
C6H10 1,5-Hexadiene 29 Bg 264 186 -78 1.421
COBr2 Carbonic dibromide 4 B1 757 496 -261 1.526
COBr2 Carbonic dibromide 6 B2 512 322 -190 1.590
CH3ONO Methyl nitrite 15 A" 186 142 -44 1.312
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 185 -42 1.228
CH2D2 methane-d2 6 B1 3013 2273 -740 1.326
CH2D2 methane-d2 8 B2 2234 3069 835 0.728
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 140 -30 1.215
LiOH lithium hydroxide 3 Π 257 211 -46 1.219
GeO2 Germanium dioxide 3 Πu 196 160 -36 1.223
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 210 66 0.687
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 340 -116 1.340
CH3OO methylperoxy radical 12 A" 170 137 -33 1.243
CH3 Methyl radical 2 A2" 606 459 -147 1.320
CH3 Methyl radical 2 A2" 606 459 -147 1.320
CH3 Methyl radical 2 A2" 606 459 -147 1.320
CH3 Methyl radical 2 A2" 606 459 -147 1.320
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 105 -253 3.421
SO2F2 Sulfuryl fluoride 4 A1 385 320 -65 1.202
SO2F2 Sulfuryl fluoride 5 A2 388 320 -68 1.211
CH2OH Hydroxymethyl radical 9 A 234 446 212 0.525
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 872 -264 1.303
OH- hydroxide anion 1 Σ 3738 3301 -437 1.133
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 158 -106 1.669
C4H6 Methylenecyclopropane 17 B1 360 273 -87 1.320
C2Cl2 dichloroacetylene 4 Πg 333 202 -131 1.652
C2Cl2+ dichloroacetylene cation 5 Πu 233 176 -57 1.325
ClFO3 Perchloryl fluoride 6 E 405 320 -85 1.267
ClFO3 Perchloryl fluoride 5 E 589 490 -99 1.202
ClFO3 Perchloryl fluoride 3 A1 549 455 -94 1.206
HClO4 perchloric acid 12 A" 191 149 -42 1.279
HClO4 perchloric acid 11 A" 408 337 -71 1.210
HClO4 perchloric acid 8 A' 405 333 -72 1.215
HClO4 perchloric acid 7 A' 548 456 -92 1.201
SOCl2 thionyl chloride 4 A' 194 158 -36 1.229
BF3+ boron trifluoride cation 4 E' 411 268 -143 1.531
BF3+ boron trifluoride cation 3 E' 1662 1131 -531 1.470
SF4 Sulfur tetrafluoride 4 A1 228 171 -57 1.336
MgF2 Magnesium fluoride 3 Πu 165 133 -32 1.242
F2SO Thionyl Fluoride 4 A' 378 306 -72 1.234
AsH3+ Arsine cation 2 A1 452 675 223 0.670
SO2Cl2 Sulfuryl chloride 4 A1 218 180 -38 1.210
BrF3 Bromine trifluoride 3 A1 242 196 -46 1.235
HSO3F Fluorosulfonic acid 11 A 390 317 -73 1.232
BrF5 bromine pentafluoride 3 A1 369 304 -65 1.214
BrF5 bromine pentafluoride 6 B2 281 188 -93 1.492
BrF5 bromine pentafluoride 8 E 415 340 -75 1.220
ClF3 Chlorine trifluoride 3 A1 328 258 -70 1.272
ClF3 Chlorine trifluoride 6 B2 442 355 -87 1.245
Cl2O Dichlorine monoxide 3 B2 686 551 -135 1.245
N2O4 Dinitrogen tetroxide 9 B2u 265 189 -76 1.404
NCl3 nitrogen trichloride 3 E 642 513 -129 1.252
PCl5 Phosphorus pentachloride 2 A1' 370 259 -111 1.427
PCl5 Phosphorus pentachloride 7 E' 100 82 -18 1.226
C3 carbon trimer 3 Πu 63 110 46 0.579
C3 carbon trimer 3 Πu 63 110 46 0.579
C3 carbon trimer 3 Πu 63 110 46 0.579
C3 carbon trimer 3 Πu 63 110 46 0.579
CaOH Calcium monohydroxide 2 Σ 353 601 248 0.587
CaOH Calcium monohydroxide 3 Π 609 294 -315 2.072
C4 Carbon tetramer 4 Πg 323 209 -114 1.548
N2O3 Dinitrogen trioxide 9 A" 63 140 77 0.449
Cu2 Copper dimer 1 Σg 265 410 146 0.645
SiH- silicon monohydride anion 1 Σ 2175 1730 -445 1.257
SiH- silicon monohydride anion 1 Σ 2175 1730 -445 1.257
SiH- silicon monohydride anion 1 Σ 2175 1730 -445 1.257
SiH- silicon monohydride anion 1 Σ 2175 1730 -445 1.257
SF5Cl sulfur chloropentafluoride 5 B1 625 431 -194 1.451
SF5Cl sulfur chloropentafluoride 7 B2 505 287 -218 1.760
SF5Cl sulfur chloropentafluoride 11 E 397 225 -172 1.762
SF2 sulfur difluoride 2 A1 355 294 -61 1.206
ZnH2 Zinc hydride 3 Πu 633 482 -150 1.312
H2OH2O water dimer 12 A" 88 -134 -222 -0.659
B2H6 Diborane 14 B2u 368 298 -70 1.234
Mg2 Magnesium diatomic 1 Σg 51 103 52 0.498
Mg2 Magnesium diatomic 1 Σg 51 103 52 0.498
ClONO2 Chlorine nitrate 7 A' 273 222 -52 1.233
GeH2 germylene 1 A1 1856 901 -955 2.060
GeH2 germylene 2 A1 916 1715 799 0.534
H2OH2O water dimer 6 A' 311 496 185 0.627
H2OH2O water dimer 7 A' 143 252 109 0.568
H2OH2O water dimer 11 A" 108 190 82 0.569
H2POH Phosphinous acid 9 A" 375 226 -149 1.659
Mg2 Magnesium diatomic 1 Σg 51 103 52 0.498
Mg2 Magnesium diatomic 1 Σg 51 103 52 0.498
BrOBr Bromine oxide 3 B2 629 523 -106 1.203
ZnCH3 Zinc monomethyl 6 E 315 599 284 0.526