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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 B3PW91/6-31G(2df,p)
Calculated values were scaled by 0.9614.

Species Name mode Symmetry Experiment Theory difference ratio
CH3COOH Acetic acid 18 A" 93 74 -19 1.254
CH3OH Methyl alcohol 12 A" 200 311 111 0.642
CH3OH Methyl alcohol 12 A" 200 310 110 0.645
CH3OH Methyl alcohol 12 A" 200 311 111 0.642
CH3OH Methyl alcohol 12 A" 200 310 110 0.645
CH3CONH2 Acetamide 20 A 259 169 -89 1.528
C3H4O2 β–Propiolactone 21 A" 113 178 65 0.633
C2H6O2S Dimethyl sulfone 20 B1 262 201 -61 1.305
CHONH2 formamide 12 A" 289 169 -120 1.708
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 228 -48 1.210
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 228 -48 1.210
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 228 -48 1.210
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 228 -48 1.210
CH3COCl Acetyl Chloride 15 A" 166 134 -32 1.242
CBr2F2 Methane, dibromodifluoro- 3 A1 140 334 194 0.419
C2F6 hexafluoroethane 4 A1u 68 56 -12 1.216
C3F8 perfluoropropane 13 A2 276 209 -67 1.319
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 523 -109 1.208
C6H4O2 parabenzoquinone 30 B3u 109 90 -18 1.203
C3H6O 2-Propen-1-ol 22 A 377 310 -67 1.216
C3H6O 2-Propen-1-ol 24 A 188 112 -76 1.680
CH3OCHO methyl formate 18 A" 130 104 -26 1.250
C4H8O Furan, tetrahydro- 17 A 286 237 -49 1.209
C5H8 Cyclopentene 18 A' 254 133 -121 1.910
C4H8O2 1,4-Dioxane 19 Au 288 237 -51 1.217
C2H4O3 trioxolane124 21 B 193 156 -37 1.241
C4H6O2 2,3-Butanedione 9 Ag 614 504 -110 1.217
C4H6O2 2,3-Butanedione 13 Au 1111 909 -202 1.222
C4H6O2 2,3-Butanedione 21 Bg 240 101 -139 2.370
C2H3NO3 Oxamic acid 21 A" 162 70 -92 2.316
HCNO fulminic acid 5 Π 224 118 -106 1.897
C6H4 Benzyne 24 B2 472 349 -123 1.351
C2H3NO3 Oxamic acid 18 A" 745 619 -126 1.203
C5H12 Propane, 2,2-dimethyl- 12 T1 203 298 95 0.682
C2H3NO3 Oxamic acid 3 A' 2600 3481 881 0.747
C2H3NO3 Oxamic acid 15 A' 328 256 -72 1.280
C2H3NO3 Oxamic acid 16 A" 984 814 -170 1.209
C2H3NO3 Oxamic acid 17 A" 815 662 -153 1.231
Zn(CH3)2 dimethyl zinc 11 E' 134 99 -35 1.349
COBr2 Carbonic dibromide 4 B1 757 522 -235 1.450
COBr2 Carbonic dibromide 6 B2 512 346 -166 1.481
C5H8 1,4-Pentadiene 16 A 137 283 146 0.485
C6H10 1,5-Hexadiene 14 Ag 351 253 -98 1.387
C6H10 1,5-Hexadiene 29 Bg 264 191 -73 1.385
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 185 -42 1.225
CH2D2 methane-d2 6 B1 3013 2257 -756 1.335
CH2D2 methane-d2 8 B2 2234 3049 815 0.733
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 138 -32 1.228
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 347 -109 1.314
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 142 -29 1.202
CH3OCH2CN Methoxyacetonitrile 15 A' 243 176 -67 1.380
CH3OCH2CN Methoxyacetonitrile 24 A" 113 85 -28 1.334
CH3OO methylperoxy radical 12 A" 170 124 -46 1.368
CH3 Methyl radical 2 A2" 606 455 -152 1.333
CH3 Methyl radical 2 A2" 606 455 -152 1.333
CH3 Methyl radical 2 A2" 606 455 -152 1.333
CH3 Methyl radical 2 A2" 606 455 -152 1.333
CH2OH Hydroxymethyl radical 9 A 234 421 187 0.555
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 861 -275 1.320
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 149 -115 1.773
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 100 -258 3.592
C4H6 Methylenecyclopropane 17 B1 360 290 -70 1.240
BF3+ boron trifluoride cation 3 E' 1662 984 -677 1.688
BF3+ boron trifluoride cation 4 E' 411 19 -392 21.391
GaF3 Gallium trifluoride 4 E' 192 110 -82 1.746
C2Cl2+ dichloroacetylene cation 5 Πu 233 186 -47 1.252
ZnCN Zinc monocyanide 3 Π 212 129 -83 1.638
CaF2 Calcium difluoride 2 A1 120 93 -27 1.295
PCl5 Phosphorus pentachloride 2 A1' 370 275 -95 1.346
N2O3 Dinitrogen trioxide 9 A" 63 143 80 0.440
CaOH Calcium monohydroxide 2 Σ 353 616 263 0.573
CaOH Calcium monohydroxide 3 Π 609 332 -277 1.836
Cu2 Copper dimer 1 Σg 265 405 141 0.653
SiH- silicon monohydride anion 1 Σ 2175 1777 -398 1.224
SiH- silicon monohydride anion 1 Σ 2175 1777 -398 1.224
SiH- silicon monohydride anion 1 Σ 2175 1777 -398 1.224
SiH- silicon monohydride anion 1 Σ 2175 1777 -398 1.224
C3 carbon trimer 3 Πu 63 128 65 0.494
ZnH2 Zinc hydride 3 Πu 633 391 -242 1.618
ClOO chloroperoxy radical 3 A' 201 87 -114 2.310
SF5Cl sulfur chloropentafluoride 5 B1 625 473 -152 1.320
SF5Cl sulfur chloropentafluoride 7 B2 505 317 -188 1.595
SF5Cl sulfur chloropentafluoride 11 E 397 250 -147 1.586
GeH2 germylene 1 A1 1856 916 -940 2.026
GeH2 germylene 2 A1 916 1882 966 0.487
Mg2 Magnesium diatomic 1 Σg 51 87 36 0.589
Mg2 Magnesium diatomic 1 Σg 51 87 36 0.589
Mg2 Magnesium diatomic 1 Σg 51 87 36 0.589
Mg2 Magnesium diatomic 1 Σg 51 87 36 0.589
Cl3- trichloride anion 2 Σu 327 267 -60 1.224
H2OH2O water dimer 7 A' 143 206 63 0.696
H2OH2O water dimer 8 A' 103 155 52 0.664
H2OH2O water dimer 11 A" 108 168 60 0.643
H2OH2O water dimer 12 A" 88 56 -32 1.585
H2POH Phosphinous acid 9 A" 375 258 -117 1.454
ZnCH3 Zinc monomethyl 6 E 315 574 259 0.549