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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
CH3COOH Acetic acid 18 A" 93 63 -30 1.477
CH3CONH2 Acetamide 20 A 259 75 -183 3.428
C3H4O2 β–Propiolactone 21 A" 113 178 65 0.634
CH3OH Methyl alcohol 12 A" 200 335 135 0.596
CH3OH Methyl alcohol 12 A" 200 333 133 0.600
CH3OH Methyl alcohol 12 A" 200 335 135 0.596
CH3OH Methyl alcohol 12 A" 200 333 133 0.600
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
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
C3F8 perfluoropropane 13 A2 276 205 -71 1.346
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 61 -14 1.232
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 522 -110 1.210
C3H6O 2-Propen-1-ol 22 A 377 312 -66 1.211
C3H6O 2-Propen-1-ol 24 A 188 114 -74 1.654
CH3OCHO methyl formate 18 A" 130 97 -33 1.336
C3H2N2 Malononitrile 6 A1 167 137 -30 1.217
C2F4 Tetrafluoroethylene 7 B2g 508 414 -94 1.227
C5H8 Cyclopentene 18 A' 254 140 -114 1.818
C2H4O3 trioxolane124 21 B 193 155 -38 1.245
C4H4N2 Pyridazine 13 A2 421 340 -81 1.236
C2H2N4 sym-tetrazine 18 B3u 254 109 -145 2.328
C2H2N4 sym-tetrazine 5 Au 335 269 -66 1.244
C4H6O2 2,3-Butanedione 21 Bg 240 87 -153 2.751
C4H6O2 2,3-Butanedione 9 Ag 614 497 -117 1.235
C4H6O2 2,3-Butanedione 13 Au 1111 899 -212 1.236
C2H3NO3 Oxamic acid 15 A' 328 256 -72 1.283
C2H3NO3 Oxamic acid 16 A" 984 774 -210 1.272
C2H3NO3 Oxamic acid 17 A" 815 670 -145 1.216
C2H3NO3 Oxamic acid 21 A" 162 71 -91 2.286
C5H12 Propane, 2,2-dimethyl- 12 T1 203 312 109 0.652
C2H3NO3 Oxamic acid 3 A' 2600 3466 866 0.750
C3O2 Carbon suboxide 7 Πu 61 123 62 0.495
C5H8 1,4-Pentadiene 16 A 137 286 149 0.479
C5H8 1,4-Pentadiene 17 A 102 84 -18 1.214
C6H10 1,5-Hexadiene 14 Ag 351 254 -97 1.382
C6H10 1,5-Hexadiene 29 Bg 264 187 -77 1.413
COBr2 Carbonic dibromide 4 B1 757 496 -261 1.525
COBr2 Carbonic dibromide 6 B2 512 322 -190 1.589
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 185 -42 1.228
CH3ONO Methyl nitrite 15 A" 186 136 -50 1.365
CH2D2 methane-d2 6 B1 3013 2276 -737 1.324
CH2D2 methane-d2 8 B2 2234 3074 840 0.727
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, (Z)- 22 A' 144 208 64 0.693
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 340 -116 1.339
CH3OO methylperoxy radical 12 A" 170 130 -40 1.310
CH3 Methyl radical 2 A2" 606 462 -144 1.311
CH3 Methyl radical 2 A2" 606 462 -144 1.311
CH3 Methyl radical 2 A2" 606 462 -144 1.311
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)- 19 A2 264 157 -107 1.676
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 870 -266 1.306
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
SOCl2 thionyl chloride 4 A' 194 158 -36 1.228
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
C2Cl2 dichloroacetylene 4 Πg 333 202 -131 1.651
C2Cl2+ dichloroacetylene cation 5 Πu 233 176 -57 1.324
HClO4 perchloric acid 7 A' 548 457 -91 1.200
HClO4 perchloric acid 8 A' 405 333 -72 1.215
HClO4 perchloric acid 11 A" 408 336 -72 1.214
HClO4 perchloric acid 12 A" 191 132 -59 1.449
SF4 Sulfur tetrafluoride 4 A1 228 171 -57 1.335
BF3+ boron trifluoride cation 3 E' 1662 1131 -530 1.469
BF3+ boron trifluoride cation 4 E' 411 269 -142 1.530
BrF3 Bromine trifluoride 3 A1 242 196 -46 1.234
MgF2 Magnesium fluoride 3 Πu 165 133 -32 1.241
F2SO Thionyl Fluoride 4 A' 378 306 -71 1.233
ClF3 Chlorine trifluoride 6 B2 442 355 -87 1.244
SO2Cl2 Sulfuryl chloride 4 A1 218 180 -38 1.209
AsH3+ Arsine cation 2 A1 452 665 213 0.680
ClF3 Chlorine trifluoride 3 A1 328 258 -70 1.271
NCl3 nitrogen trichloride 3 E 642 513 -129 1.251
Cl2O Dichlorine monoxide 3 B2 686 551 -135 1.244
N2O4 Dinitrogen tetroxide 9 B2u 265 189 -76 1.403
PCl5 Phosphorus pentachloride 2 A1' 370 259 -111 1.426
PCl5 Phosphorus pentachloride 7 E' 100 82 -18 1.226
N2O3 Dinitrogen trioxide 9 A" 63 140 77 0.449
BrF5 bromine pentafluoride 3 A1 369 304 -65 1.213
BrF5 bromine pentafluoride 6 B2 281 188 -93 1.491
BrF5 bromine pentafluoride 8 E 415 340 -75 1.219
C3 carbon trimer 3 Πu 63 110 46 0.578
C3 carbon trimer 3 Πu 63 110 46 0.579
C3 carbon trimer 3 Πu 63 110 46 0.578
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 609 293 -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
SiH- silicon monohydride anion 1 Σ 2175 1742 -433 1.249
SiH- silicon monohydride anion 1 Σ 2175 1741 -434 1.249
SiH- silicon monohydride anion 1 Σ 2175 1742 -433 1.249
SF5Cl sulfur chloropentafluoride 5 B1 625 431 -194 1.451
SF5Cl sulfur chloropentafluoride 7 B2 505 287 -218 1.759
SF5Cl sulfur chloropentafluoride 11 E 397 225 -172 1.761
SF2 sulfur difluoride 2 A1 355 295 -60 1.205
B2H6 Diborane 14 B2u 368 304 -64 1.211
ZnH2 Zinc hydride 3 Πu 633 464 -169 1.364
BrOBr Bromine oxide 3 B2 629 523 -106 1.202
ClONO2 Chlorine nitrate 7 A' 273 222 -51 1.232
GeH2 germylene 1 A1 1856 908 -948 2.044
GeH2 germylene 2 A1 916 1927 1011 0.475
ZnCH3 Zinc monomethyl 6 E 315 601 286 0.524
H2OH2O water dimer 6 A' 311 475 164 0.654
H2OH2O water dimer 7 A' 143 236 93 0.605
H2OH2O water dimer 11 A" 108 186 78 0.581
H2OH2O water dimer 12 A" 88 -116 -204 -0.757
H2POH Phosphinous acid 9 A" 375 230 -146 1.634
Mg2 Magnesium diatomic 1 Σg 51 103 52 0.497
Mg2 Magnesium diatomic 1 Σg 51 103 52 0.497
Mg2 Magnesium diatomic 1 Σg 51 103 52 0.497
Mg2 Magnesium diatomic 1 Σg 51 103 52 0.497