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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 LSDA/6-31G**
Calculated values were scaled by 0.9813.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 182 69 0.620
CH3COOH Acetic acid 18 A" 93 71 -22 1.308
C2H6O2S Dimethyl sulfone 20 B1 262 216 -46 1.212
C2H6O2S Dimethyl sulfone 13 A2 326 264 -62 1.235
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 312 98 0.686
CH3OH Methyl alcohol 12 A" 200 341 141 0.587
CH3OH Methyl alcohol 12 A" 200 339 139 0.590
CH3OH Methyl alcohol 12 A" 200 341 141 0.587
CH3OH Methyl alcohol 12 A" 200 339 139 0.590
C2H2 Acetylene 4 Πg 612 505 -107 1.213
CH3COCl Acetyl Chloride 15 A" 166 131 -35 1.269
CBr2F2 Methane, dibromodifluoro- 3 A1 140 329 189 0.425
C2F6 hexafluoroethane 4 A1u 68 29 -39 2.327
C3F8 perfluoropropane 13 A2 276 199 -77 1.384
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 60 -15 1.256
CH3OCHO methyl formate 18 A" 130 88 -42 1.471
C3H6O 2-Propen-1-ol 22 A 377 304 -73 1.241
C3H6O 2-Propen-1-ol 24 A 188 119 -69 1.584
C3H2N2 Malononitrile 6 A1 167 137 -30 1.218
C2F4 Tetrafluoroethylene 9 B2u 218 181 -37 1.204
C5H8 Cyclopentene 18 A' 254 165 -89 1.542
C4H4N2 Pyridazine 13 A2 421 336 -85 1.251
C2H2N4 sym-tetrazine 5 Au 335 258 -77 1.298
C2H2N4 sym-tetrazine 18 B3u 254 -4 -258 -60.003
C4H6O2 2,3-Butanedione 9 Ag 614 508 -106 1.209
C4H6O2 2,3-Butanedione 13 Au 1111 874 -237 1.272
C4H6O2 2,3-Butanedione 16 Au 48 -34 -82 -1.421
C4H6O2 2,3-Butanedione 21 Bg 240 47 -193 5.073
C5H12 Propane, 2,2-dimethyl- 12 T1 203 323 120 0.629
C3O2 Carbon suboxide 7 Πu 61 139 78 0.437
C2H3NO3 Oxamic acid 3 A' 2600 3424 824 0.759
C2H3NO3 Oxamic acid 15 A' 328 257 -71 1.279
C2H3NO3 Oxamic acid 16 A" 984 787 -197 1.250
C2H3NO3 Oxamic acid 21 A" 162 87 -75 1.868
C5H8 1,4-Pentadiene 16 A 137 284 147 0.483
C6H10 1,5-Hexadiene 14 Ag 351 269 -82 1.305
C6H10 1,5-Hexadiene 29 Bg 264 214 -50 1.232
COBr2 Carbonic dibromide 4 B1 757 509 -248 1.487
COBr2 Carbonic dibromide 6 B2 512 335 -177 1.531
CH3ONO Methyl nitrite 15 A" 186 154 -32 1.208
CH3SSCH3 Disulfide, dimethyl 13 A 117 73 -44 1.596
C2F2 difluoroacetylene 4 Πg 270 166 -104 1.627
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 180 -47 1.259
CH2D2 methane-d2 6 B1 3013 2280 -733 1.322
CH2D2 methane-d2 8 B2 2234 3078 844 0.726
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 136 -34 1.252
CuO Copper Monoxide 1 Σ 640 931 291 0.687
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 216 72 0.667
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 216 72 0.666
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 216 72 0.667
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 216 72 0.666
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 341 -115 1.339
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 340 -116 1.340
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 341 -115 1.339
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 340 -116 1.340
CH3OO methylperoxy radical 12 A" 170 126 -44 1.351
CH3 Methyl radical 2 A2" 606 486 -120 1.248
CH3 Methyl radical 2 A2" 606 482 -124 1.257
CH3 Methyl radical 2 A2" 606 486 -120 1.248
CH3 Methyl radical 2 A2" 606 482 -124 1.257
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 109 -249 3.288
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 166 -98 1.594
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 875 -261 1.298
CH2OH Hydroxymethyl radical 9 A 234 427 193 0.548
C4H6 Methylenecyclopropane 17 B1 360 280 -80 1.285
BF3+ boron trifluoride cation 4 E' 411 267 -144 1.540
BF3+ boron trifluoride cation 3 E' 1662 1224 -438 1.358
ClFO3 Perchloryl fluoride 6 E 405 334 -71 1.214
HClO4 perchloric acid 12 A" 191 127 -64 1.510
C2Cl2+ dichloroacetylene cation 5 Πu 233 178 -55 1.310
C2Cl2 dichloroacetylene 4 Πg 333 245 -88 1.358
SF4 Sulfur tetrafluoride 4 A1 228 177 -51 1.290
HSO3F Fluorosulfonic acid 11 A 390 325 -65 1.202
MgF2 Magnesium fluoride 3 Πu 165 134 -31 1.232
BeF2 Beryllium fluoride 3 Πu 343 283 -60 1.211
BrF5 bromine pentafluoride 6 B2 281 198 -83 1.422
CaF2 Calcium difluoride 2 A1 120 19 -101 6.250
N2O4 Dinitrogen tetroxide 9 B2u 265 217 -48 1.219
N2O3 Dinitrogen trioxide 9 A" 63 151 88 0.417
PCl5 Phosphorus pentachloride 2 A1' 370 279 -91 1.325
C3 carbon trimer 3 Πu 63 138 75 0.458
C3 carbon trimer 3 Πu 63 137 74 0.461
C3 carbon trimer 3 Πu 63 138 75 0.458
C3 carbon trimer 3 Πu 63 137 74 0.461
SF5Cl sulfur chloropentafluoride 11 E 397 233 -164 1.706
B2Cl4 Diboron tetrachloride 9 E 104 86 -18 1.209
SiH- silicon monohydride anion 1 Σ 2175 1752 -423 1.241
SiH- silicon monohydride anion 1 Σ 2175 1752 -423 1.241
SiH- silicon monohydride anion 1 Σ 2175 1752 -423 1.241
SiH- silicon monohydride anion 1 Σ 2175 1752 -423 1.241
SF5Cl sulfur chloropentafluoride 5 B1 625 444 -181 1.407
SF5Cl sulfur chloropentafluoride 7 B2 505 297 -208 1.698
H3O+ hydronium 2 A1 954 693 -262 1.378
ZnH2 Zinc hydride 3 Πu 633 470 -163 1.347
GeH2 germylene 1 A1 1856 895 -961 2.074
GeH2 germylene 2 A1 916 1966 1050 0.466
H2OH2O water dimer 6 A' 311 585 274 0.531
H2OH2O water dimer 7 A' 143 327 184 0.437
H2OH2O water dimer 10 A" 523 785 262 0.666
H2OH2O water dimer 11 A" 108 205 97 0.527
H2OH2O water dimer 12 A" 88 -206 -294 -0.428
ClOO chloroperoxy radical 3 A' 201 316 115 0.637
H2POH Phosphinous acid 9 A" 375 244 -132 1.540
B2H6 Diborane 14 B2u 368 262 -106 1.403
Mg2 Magnesium diatomic 1 Σg 51 119 68 0.430
Mg2 Magnesium diatomic 1 Σg 51 119 68 0.430
Mg2 Magnesium diatomic 1 Σg 51 119 68 0.430
Mg2 Magnesium diatomic 1 Σg 51 119 68 0.430
ZnCH3 Zinc monomethyl 6 E 315 594 279 0.531