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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 0.621
CH3CONH2 Acetamide 20 A 259 209 -50 1.239
C2H6O2S Dimethyl sulfone 13 A2 326 264 -62 1.236
C2H6O2S Dimethyl sulfone 20 B1 262 217 -45 1.206
CH3OH Methyl alcohol 12 A" 200 350 150 0.571
CH3OH Methyl alcohol 12 A" 200 349 149 0.573
CH3OH Methyl alcohol 12 A" 200 350 150 0.571
CH3OH Methyl alcohol 12 A" 200 349 149 0.573
C2H2 Acetylene 4 Πg 612 473 -139 1.295
CH3COOH Acetic acid 18 A" 93 68 -25 1.363
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 314 100 0.682
CH3COCl Acetyl Chloride 15 A" 166 132 -34 1.260
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 61 -14 1.233
C3H6O 2-Propen-1-ol 22 A 377 306 -72 1.234
C3H6O 2-Propen-1-ol 24 A 188 119 -69 1.576
CH3OCHO methyl formate 18 A" 130 103 -27 1.263
C3H2N2 Malononitrile 6 A1 167 137 -30 1.215
C2F4 Tetrafluoroethylene 9 B2u 218 181 -37 1.204
C5H8 Cyclopentene 18 A' 254 165 -89 1.537
C4H4N2 Pyridazine 13 A2 421 337 -84 1.248
C2H2N4 sym-tetrazine 5 Au 335 260 -75 1.288
C2H2N4 sym-tetrazine 18 B3u 254 28 -226 9.189
C5H12 Propane, 2,2-dimethyl- 12 T1 203 323 120 0.628
C4H2 Diacetylene 8 Πu 630 522 -108 1.206
C4H6O2 2,3-Butanedione 9 Ag 614 508 -106 1.208
C4H6O2 2,3-Butanedione 13 Au 1111 887 -224 1.253
C4H6O2 2,3-Butanedione 16 Au 48 26 -22 1.818
C4H6O2 2,3-Butanedione 21 Bg 240 69 -171 3.460
C3O2 Carbon suboxide 7 Πu 61 139 78 0.437
C2H3NO3 Oxamic acid 3 A' 2600 3420 820 0.760
C2H3NO3 Oxamic acid 15 A' 328 257 -71 1.276
C2H3NO3 Oxamic acid 16 A" 984 790 -194 1.246
C2H3NO3 Oxamic acid 21 A" 162 86 -76 1.875
C5H8 1,4-Pentadiene 16 A 137 285 148 0.481
C6H10 1,5-Hexadiene 14 Ag 351 270 -81 1.302
C6H10 1,5-Hexadiene 29 Bg 264 214 -50 1.233
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' 227 181 -46 1.255
CH3SSCH3 Disulfide, dimethyl 13 A 117 71 -46 1.644
CH2D2 methane-d2 8 B2 2234 3076 842 0.726
CH2D2 methane-d2 6 B1 3013 2278 -735 1.323
C2F2 difluoroacetylene 4 Πg 270 166 -104 1.627
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' 144 218 74 0.660
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 218 74 0.660
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 218 74 0.660
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 218 74 0.660
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 341 -115 1.338
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 340 -116 1.339
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 341 -115 1.338
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 340 -116 1.339
CH3OO methylperoxy radical 12 A" 170 134 -36 1.269
CH3 Methyl radical 2 A2" 606 479 -127 1.265
CH3 Methyl radical 2 A2" 606 476 -131 1.275
CH3 Methyl radical 2 A2" 606 479 -127 1.265
CH3 Methyl radical 2 A2" 606 476 -131 1.275
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 879 -257 1.293
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 166 -98 1.590
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 109 -249 3.291
CH2OH Hydroxymethyl radical 9 A 234 444 210 0.527
C2Cl2 dichloroacetylene 4 Πg 333 245 -88 1.358
C2Cl2+ dichloroacetylene cation 5 Πu 233 178 -55 1.310
C4H6 Methylenecyclopropane 17 B1 360 279 -81 1.289
HClO4 perchloric acid 12 A" 191 151 -40 1.268
BF3+ boron trifluoride cation 3 E' 1662 1224 -438 1.358
BF3+ boron trifluoride cation 4 E' 411 267 -144 1.540
ClFO3 Perchloryl fluoride 6 E 405 334 -71 1.214
MgF2 Magnesium fluoride 3 Πu 165 134 -31 1.232
HSO3F Fluorosulfonic acid 11 A 390 324 -66 1.205
CaF2 Calcium difluoride 2 A1 120 19 -101 6.250
BeF2 Beryllium fluoride 3 Πu 343 283 -60 1.211
BrF5 bromine pentafluoride 6 B2 281 198 -83 1.422
SF4 Sulfur tetrafluoride 4 A1 228 177 -51 1.290
N2O4 Dinitrogen tetroxide 9 B2u 265 217 -48 1.219
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
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 1743 -432 1.248
SiH- silicon monohydride anion 1 Σ 2175 1743 -432 1.248
SiH- silicon monohydride anion 1 Σ 2175 1743 -432 1.248
SiH- silicon monohydride anion 1 Σ 2175 1743 -432 1.248
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
B2Cl4 Diboron tetrachloride 9 E 104 86 -18 1.209
ClOO chloroperoxy radical 3 A' 201 316 115 0.637
ZnH2 Zinc hydride 3 Πu 633 490 -142 1.291
H2POH Phosphinous acid 9 A" 375 244 -131 1.539
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
B2H6 Diborane 14 B2u 368 257 -111 1.434
GeH2 germylene 1 A1 1856 892 -964 2.081
GeH2 germylene 2 A1 916 1745 829 0.525
H2OH2O water dimer 6 A' 311 611 300 0.509
H2OH2O water dimer 7 A' 143 341 198 0.419
H2OH2O water dimer 10 A" 523 806 283 0.649
H2OH2O water dimer 11 A" 108 207 99 0.522
H2OH2O water dimer 12 A" 88 -196 -284 -0.449
ZnCH3 Zinc monomethyl 6 E 315 593 278 0.532