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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 B3LYP/6-31G**
Calculated values were scaled by 0.9608.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 323 123 0.620
CH3OH Methyl alcohol 12 A" 200 323 123 0.620
CH3OH Methyl alcohol 12 A" 200 323 123 0.620
CH3OH Methyl alcohol 12 A" 200 323 123 0.620
CH3COOH Acetic acid 18 A" 93 75 -18 1.241
CH3CONH2 Acetamide 20 A 259 106 -153 2.446
C3H4O2 β–Propiolactone 21 A" 113 177 64 0.638
CH3COCH3 Acetone 12 A2 77 39 -38 1.974
C2H6O2S Dimethyl sulfone 13 A2 326 268 -58 1.215
C2H6O2S Dimethyl sulfone 20 B1 262 206 -56 1.272
CHONH2 formamide 12 A" 289 157 -132 1.840
CH3COCl Acetyl Chloride 15 A" 166 130 -36 1.274
CH3NO2 Methane, nitro- 11 A" 1583 3061 1478 0.517
CBr2F2 Methane, dibromodifluoro- 3 A1 140 313 173 0.448
C2F6 hexafluoroethane 4 A1u 68 45 -23 1.510
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 62 -13 1.212
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 522 -110 1.210
C3F8 perfluoropropane 13 A2 276 210 -66 1.313
CH3COOCH3 methyl acetate 27 A" 110 44 -66 2.497
CH2BrCH2Br Ethane, 1,2-dibromo- 10 Au 118 97 -21 1.222
C3H6O 2-Propen-1-ol 24 A 188 112 -76 1.680
C4H8O2 1,4-Dioxane 19 Au 288 239 -49 1.206
C5H8 Cyclopentene 18 A' 254 134 -120 1.894
C2H3N3 1H-1,2,4-Triazole 18 A" 640 530 -110 1.208
C2H4O3 trioxolane124 21 B 193 156 -37 1.239
C4H6O2 2,3-Butanedione 9 Ag 614 503 -111 1.220
C4H6O2 2,3-Butanedione 13 Au 1111 924 -187 1.203
C4H6O2 2,3-Butanedione 21 Bg 240 101 -139 2.380
C6H4 Benzyne 24 B2 472 389 -83 1.212
C3H6O Oxetane 18 B1 90 63 -27 1.424
C3H6O Oxetane 23 B2 1228 1005 -223 1.221
C5H12 Propane, 2,2-dimethyl- 12 T1 203 299 96 0.678
C2H3NO3 Oxamic acid 3 A' 2600 3462 862 0.751
C2H3NO3 Oxamic acid 15 A' 328 260 -68 1.260
C2H3NO3 Oxamic acid 16 A" 984 784 -200 1.255
C2H3NO3 Oxamic acid 17 A" 815 657 -158 1.240
C2H3NO3 Oxamic acid 18 A" 745 612 -133 1.218
C2H3NO3 Oxamic acid 21 A" 162 67 -95 2.410
C3H6O Oxetane 12 A2 986 811 -175 1.215
C3O2 Carbon suboxide 7 Πu 61 124 63 0.491
C5H8 1,4-Pentadiene 16 A 137 287 150 0.477
C6H10 1,5-Hexadiene 14 Ag 351 257 -94 1.367
C6H10 1,5-Hexadiene 29 Bg 264 181 -83 1.456
COBr2 Carbonic dibromide 4 B1 757 496 -261 1.527
COBr2 Carbonic dibromide 6 B2 512 324 -188 1.581
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 187 -40 1.213
CH3SSCH3 Disulfide, dimethyl 13 A 117 95 -22 1.233
CH2D2 methane-d2 6 B1 3013 2250 -763 1.339
CH2D2 methane-d2 8 B2 2234 3038 804 0.735
C2F2 difluoroacetylene 4 Πg 270 194 -76 1.389
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 209 65 0.688
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 209 65 0.689
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 209 65 0.688
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 209 65 0.689
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 346 -110 1.318
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 346 -110 1.318
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 346 -110 1.318
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 346 -110 1.318
CH3OO methylperoxy radical 12 A" 170 129 -41 1.321
CH3 Methyl radical 2 A2" 606 444 -163 1.366
CH3 Methyl radical 2 A2" 606 444 -163 1.366
CH3 Methyl radical 2 A2" 606 444 -163 1.366
CH3 Methyl radical 2 A2" 606 444 -163 1.366
CH2OH Hydroxymethyl radical 9 A 234 422 188 0.554
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 864 -272 1.315
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 151 -113 1.754
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 102 -256 3.524
C4H6 Methylenecyclopropane 17 B1 360 283 -77 1.274
C2Cl2 dichloroacetylene 4 Πg 333 277 -56 1.203
C2Cl2+ dichloroacetylene cation 5 Πu 233 177 -56 1.318
ClFO3 Perchloryl fluoride 6 E 405 333 -72 1.218
HClO4 perchloric acid 12 A" 191 131 -60 1.455
BF3+ boron trifluoride cation 3 E' 1662 975 -687 1.705
BF3+ boron trifluoride cation 4 E' 411 119 -292 3.468
MgF2 Magnesium fluoride 3 Πu 165 132 -33 1.253
AsH3+ Arsine cation 2 A1 452 681 229 0.664
SF4 Sulfur tetrafluoride 4 A1 228 181 -47 1.256
N2O4 Dinitrogen tetroxide 9 B2u 265 220 -45 1.205
ZnCN Zinc monocyanide 3 Π 212 49 -163 4.286
BrF5 bromine pentafluoride 6 B2 281 203 -78 1.384
Cu2 Copper dimer 1 Σg 265 387 123 0.683
N2O3 Dinitrogen trioxide 9 A" 63 141 78 0.446
PCl5 Phosphorus pentachloride 2 A1' 370 257 -113 1.440
CaOH Calcium monohydroxide 2 Σ 353 601 248 0.587
CaOH Calcium monohydroxide 3 Π 609 327 -282 1.864
C3 carbon trimer 3 Πu 63 178 114 0.357
SiH- silicon monohydride anion 1 Σ 2175 1741 -434 1.249
SiH- silicon monohydride anion 1 Σ 2175 1741 -434 1.249
SiH- silicon monohydride anion 1 Σ 2175 1741 -434 1.249
SiH- silicon monohydride anion 1 Σ 2175 1741 -434 1.249
SF5Cl sulfur chloropentafluoride 5 B1 625 439 -186 1.424
SF5Cl sulfur chloropentafluoride 7 B2 505 295 -210 1.711
SF5Cl sulfur chloropentafluoride 11 E 397 231 -166 1.719
ClOO chloroperoxy radical 2 A' 414 300 -113 1.378
ClOO chloroperoxy radical 3 A' 201 122 -80 1.656
H3O+ hydronium 2 A1 954 754 -200 1.266
ZnH2 Zinc hydride 3 Πu 633 485 -147 1.304
ZnCH3 Zinc monomethyl 6 E 315 595 280 0.529
H2POH Phosphinous acid 9 A" 375 243 -132 1.545
Cl3- trichloride anion 2 Σu 327 266 -61 1.228
H2OH2O water dimer 7 A' 143 210 67 0.680
H2OH2O water dimer 11 A" 108 168 60 0.643
H2OH2O water dimer 12 A" 88 38 -50 2.329
Mg2 Magnesium diatomic 1 Σg 51 42 -9 1.203
Mg2 Magnesium diatomic 1 Σg 51 42 -9 1.203
Mg2 Magnesium diatomic 1 Σg 51 42 -9 1.203
Mg2 Magnesium diatomic 1 Σg 51 42 -9 1.203