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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
CH3OH Methyl alcohol 12 A" 200 341 141 0.587
CH3OH Methyl alcohol 12 A" 200 339 139 0.590
C2H6O2S Dimethyl sulfone 13 A2 326 264 -62 1.235
C2H6O2S Dimethyl sulfone 20 B1 262 216 -46 1.212
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
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 312 98 0.686
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
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 60 -15 1.256
C3F8 perfluoropropane 13 A2 276 199 -77 1.384
C3H6O 2-Propen-1-ol 22 A 377 304 -73 1.241
C3H6O 2-Propen-1-ol 24 A 188 119 -69 1.584
CH3OCHO methyl formate 18 A" 130 88 -42 1.471
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
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
C3O2 Carbon suboxide 7 Πu 61 139 78 0.437
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
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 180 -47 1.259
CH3ONO Methyl nitrite 15 A" 186 154 -32 1.208
C2F2 difluoroacetylene 4 Πg 270 166 -104 1.627
CH2D2 methane-d2 8 B2 2234 3078 844 0.726
CH2D2 methane-d2 6 B1 3013 2280 -733 1.322
CH3SSCH3 Disulfide, dimethyl 13 A 117 73 -44 1.596
CuO Copper Monoxide 1 Σ 640 931 291 0.687
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 136 -34 1.252
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
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 875 -261 1.298
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 166 -98 1.594
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 109 -249 3.288
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
CH2OH Hydroxymethyl radical 9 A 234 427 193 0.548
C4H6 Methylenecyclopropane 17 B1 360 280 -80 1.285
C2Cl2+ dichloroacetylene cation 5 Πu 233 178 -55 1.310
ClFO3 Perchloryl fluoride 6 E 405 334 -71 1.214
HClO4 perchloric acid 12 A" 191 127 -64 1.510
BeF2 Beryllium fluoride 3 Πu 343 283 -60 1.211
HSO3F Fluorosulfonic acid 11 A 390 325 -65 1.202
C2Cl2 dichloroacetylene 4 Πg 333 245 -88 1.358
SF4 Sulfur tetrafluoride 4 A1 228 177 -51 1.290
BF3+ boron trifluoride cation 4 E' 411 267 -144 1.540
BF3+ boron trifluoride cation 3 E' 1662 1224 -438 1.358
MgF2 Magnesium fluoride 3 Πu 165 134 -31 1.232
BrF5 bromine pentafluoride 6 B2 281 198 -83 1.422
CaF2 Calcium difluoride 2 A1 120 19 -101 6.250
PCl5 Phosphorus pentachloride 2 A1' 370 279 -91 1.325
N2O3 Dinitrogen trioxide 9 A" 63 151 88 0.417
C3 carbon trimer 3 Πu 63 138 75 0.458
C3 carbon trimer 3 Πu 63 137 74 0.461
B2Cl4 Diboron tetrachloride 9 E 104 86 -18 1.209
C3 carbon trimer 3 Πu 63 138 75 0.458
C3 carbon trimer 3 Πu 63 137 74 0.461
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
H3O+ hydronium 2 A1 954 693 -262 1.378
ZnH2 Zinc hydride 3 Πu 633 470 -163 1.347
N2O4 Dinitrogen tetroxide 9 B2u 265 217 -48 1.219
ClOO chloroperoxy radical 3 A' 201 316 115 0.637
GeH2 germylene 1 A1 1856 895 -961 2.074
GeH2 germylene 2 A1 916 1966 1050 0.466
H2POH Phosphinous acid 9 A" 375 244 -132 1.540
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
SF5Cl sulfur chloropentafluoride 5 B1 625 444 -181 1.407
SF5Cl sulfur chloropentafluoride 7 B2 505 297 -208 1.698
SF5Cl sulfur chloropentafluoride 11 E 397 233 -164 1.706
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
B2H6 Diborane 14 B2u 368 262 -106 1.403
ZnCH3 Zinc monomethyl 6 E 315 594 279 0.531