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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
CH3CONH2 Acetamide 20 A 259 155 -104 1.675
CH3COOH Acetic acid 18 A" 93 61 -32 1.528
CH3COCH3 Acetone 12 A2 77 32 -45 2.430
CH3OH Methyl alcohol 12 A" 200 345 145 0.579
CH3OH Methyl alcohol 12 A" 200 343 143 0.583
C2H6O2S Dimethyl sulfone 13 A2 326 260 -66 1.252
C2H6O2S Dimethyl sulfone 20 B1 262 207 -55 1.264
CH3OH Methyl alcohol 12 A" 200 345 145 0.579
CH3OH Methyl alcohol 12 A" 200 343 143 0.583
C3H4O2 β–Propiolactone 21 A" 113 178 65 0.635
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 5 Au 335 271 -64 1.237
C2H2N4 sym-tetrazine 18 B3u 254 113 -141 2.253
C4H2 Diacetylene 8 Πu 630 504 -126 1.250
NH2CN cyanamide 5 A' 408 589 181 0.692
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
C4H6O2 2,3-Butanedione 9 Ag 614 497 -117 1.235
C4H6O2 2,3-Butanedione 13 Au 1111 911 -200 1.220
C4H6O2 2,3-Butanedione 21 Bg 240 98 -142 2.438
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
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
C6H10 1,5-Hexadiene 14 Ag 351 254 -97 1.382
C6H10 1,5-Hexadiene 29 Bg 264 186 -78 1.421
C5H8 1,4-Pentadiene 16 A 137 287 150 0.477
C5H8 1,4-Pentadiene 17 A 102 85 -17 1.205
COBr2 Carbonic dibromide 4 B1 757 496 -261 1.526
COBr2 Carbonic dibromide 6 B2 512 322 -190 1.590
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 185 -42 1.228
CH3ONO Methyl nitrite 15 A" 186 142 -44 1.312
CH2D2 methane-d2 8 B2 2234 3069 835 0.728
CH2D2 methane-d2 6 B1 3013 2273 -740 1.326
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 140 -30 1.215
GeO2 Germanium dioxide 3 Πu 196 160 -36 1.223
LiOH lithium hydroxide 3 Π 257 211 -46 1.219
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 210 66 0.687
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 340 -116 1.340
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
CH3OO methylperoxy radical 12 A" 170 137 -33 1.243
CH2OH Hydroxymethyl radical 9 A 234 446 212 0.525
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 158 -106 1.669
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 105 -253 3.421
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 872 -264 1.303
SO2F2 Sulfuryl fluoride 4 A1 385 320 -65 1.202
SO2F2 Sulfuryl fluoride 5 A2 388 320 -68 1.211
OH- hydroxide anion 1 Σ 3738 3301 -437 1.133
C4H6 Methylenecyclopropane 17 B1 360 273 -87 1.320
HClO4 perchloric acid 8 A' 405 333 -72 1.215
HClO4 perchloric acid 11 A" 408 337 -71 1.210
HClO4 perchloric acid 12 A" 191 149 -42 1.279
ClFO3 Perchloryl fluoride 3 A1 549 455 -94 1.206
ClFO3 Perchloryl fluoride 5 E 589 490 -99 1.202
ClFO3 Perchloryl fluoride 6 E 405 320 -85 1.267
BF3+ boron trifluoride cation 3 E' 1662 1131 -531 1.470
BF3+ boron trifluoride cation 4 E' 411 268 -143 1.531
C2Cl2 dichloroacetylene 4 Πg 333 202 -131 1.652
C2Cl2+ dichloroacetylene cation 5 Πu 233 176 -57 1.325
HClO4 perchloric acid 7 A' 548 456 -92 1.201
SOCl2 thionyl chloride 4 A' 194 158 -36 1.229
MgF2 Magnesium fluoride 3 Πu 165 133 -32 1.242
F2SO Thionyl Fluoride 4 A' 378 306 -72 1.234
SF4 Sulfur tetrafluoride 4 A1 228 171 -57 1.336
Cl2O Dichlorine monoxide 3 B2 686 551 -135 1.245
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
AsH3+ Arsine cation 2 A1 452 675 223 0.670
BrF3 Bromine trifluoride 3 A1 242 196 -46 1.235
NCl3 nitrogen trichloride 3 E 642 513 -129 1.252
SO2Cl2 Sulfuryl chloride 4 A1 218 180 -38 1.210
PCl5 Phosphorus pentachloride 7 E' 100 82 -18 1.226
PCl5 Phosphorus pentachloride 2 A1' 370 259 -111 1.427
N2O3 Dinitrogen trioxide 9 A" 63 140 77 0.449
N2O4 Dinitrogen tetroxide 9 B2u 265 189 -76 1.404
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
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
Cu2 Copper dimer 1 Σg 265 410 146 0.645
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
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
SF2 sulfur difluoride 2 A1 355 294 -61 1.206
ClONO2 Chlorine nitrate 7 A' 273 222 -52 1.233
ZnH2 Zinc hydride 3 Πu 633 482 -150 1.312
B2H6 Diborane 14 B2u 368 298 -70 1.234
BrOBr Bromine oxide 3 B2 629 523 -106 1.203
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
H2OH2O water dimer 12 A" 88 -134 -222 -0.659
ZnCH3 Zinc monomethyl 6 E 315 599 284 0.526
GeH2 germylene 1 A1 1856 901 -955 2.060
GeH2 germylene 2 A1 916 1715 799 0.534
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
Mg2 Magnesium diatomic 1 Σg 51 103 52 0.498
Mg2 Magnesium diatomic 1 Σg 51 103 52 0.498