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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 B3LYPultrafine/6-31G*
Calculated values were scaled by 0.958.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 332 132 0.603
CH3OH Methyl alcohol 12 A" 200 332 132 0.603
CH3OH Methyl alcohol 12 A" 200 332 132 0.603
CH3OH Methyl alcohol 12 A" 200 332 132 0.603
CH3COOH Acetic acid 18 A" 93 76 -17 1.223
CH3CONH2 Acetamide 20 A 259 130 -129 1.998
CH3COCH3 Acetone 12 A2 77 47 -30 1.623
C3H4O2 β–Propiolactone 21 A" 113 178 65 0.636
C2H6O2S Dimethyl sulfone 13 A2 326 268 -58 1.214
C2H6O2S Dimethyl sulfone 20 B1 262 201 -61 1.301
CHONH2 formamide 12 A" 289 80 -209 3.623
CH3COCl Acetyl Chloride 15 A" 166 133 -33 1.252
C2F6 hexafluoroethane 4 A1u 68 50 -18 1.361
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 521 -111 1.213
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 62 -13 1.208
CH3COOCH3 methyl acetate 27 A" 110 54 -56 2.029
CBr2F2 Methane, dibromodifluoro- 3 A1 140 313 173 0.448
C3F8 perfluoropropane 13 A2 276 210 -66 1.316
CH2BrCH2Br Ethane, 1,2-dibromo- 10 Au 118 98 -20 1.207
C3H6O 2-Propen-1-ol 24 A 188 111 -77 1.692
C5H12 Pentane 23 A2 131 105 -26 1.246
C5H8 Cyclopentene 18 A' 254 135 -119 1.882
C2H3N3 1H-1,2,4-Triazole 18 A" 640 515 -125 1.243
CF3CN Acetonitrile, trifluoro- 4 A1 522 2297 1775 0.227
C4H6O2 2,3-Butanedione 21 Bg 240 105 -135 2.288
C4H6O2 2,3-Butanedione 9 Ag 614 502 -112 1.224
NH2CN cyanamide 5 A' 408 584 176 0.699
C3O2 Carbon suboxide 7 Πu 61 124 63 0.493
C6H4 Benzyne 24 B2 472 389 -83 1.213
C2H3NO3 Oxamic acid 3 A' 2600 3445 845 0.755
C2H3NO3 Oxamic acid 15 A' 328 258 -70 1.271
C2H3NO3 Oxamic acid 16 A" 984 783 -201 1.256
C2H3NO3 Oxamic acid 17 A" 815 660 -155 1.234
C2H3NO3 Oxamic acid 18 A" 745 612 -133 1.216
C2H3NO3 Oxamic acid 21 A" 162 64 -98 2.529
C5H8 1,4-Pentadiene 16 A 137 287 150 0.477
C6H10 1,5-Hexadiene 14 Ag 351 255 -96 1.377
C6H10 1,5-Hexadiene 29 Bg 264 175 -89 1.508
COBr2 Carbonic dibromide 4 B1 757 493 -264 1.536
COBr2 Carbonic dibromide 6 B2 512 323 -189 1.587
CH3SSCH3 Disulfide, dimethyl 13 A 117 93 -24 1.252
CH2D2 methane-d2 6 B1 3013 2244 -769 1.343
CH2D2 methane-d2 8 B2 2234 3029 795 0.737
C2F2 difluoroacetylene 4 Πg 270 194 -76 1.394
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 141 -29 1.206
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.679
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 345 -111 1.323
CH3OO methylperoxy radical 12 A" 170 135 -35 1.261
C2H5 Ethyl radical 9 A' 528 438 -90 1.205
C4H9N Cyclobutylamine 21 A' 174 137 -37 1.268
CH3 Methyl radical 2 A2" 606 435 -172 1.396
CH3 Methyl radical 2 A2" 606 435 -172 1.396
CH3 Methyl radical 2 A2" 606 435 -172 1.396
CH3 Methyl radical 2 A2" 606 435 -172 1.396
CH2OH Hydroxymethyl radical 9 A 234 432 198 0.542
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 863 -273 1.316
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 155 -109 1.707
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 103 -255 3.483
OH- hydroxide anion 1 Σ 3738 3272 -467 1.143
C4H6 Methylenecyclopropane 17 B1 360 282 -78 1.278
C2Cl2 dichloroacetylene 4 Πg 333 276 -57 1.205
ClFO3 Perchloryl fluoride 6 E 405 332 -73 1.221
BF3+ boron trifluoride cation 4 E' 411 118 -293 3.476
BF3+ boron trifluoride cation 3 E' 1662 971 -690 1.710
HClO4 perchloric acid 12 A" 191 150 -41 1.274
C2Cl2+ dichloroacetylene cation 5 Πu 233 176 -57 1.326
MgF2 Magnesium fluoride 3 Πu 165 133 -32 1.238
AsH3+ Arsine cation 2 A1 452 682 230 0.662
ZnCN Zinc monocyanide 3 Π 212 51 -161 4.151
PCl5 Phosphorus pentachloride 2 A1' 370 256 -114 1.444
N2O4 Dinitrogen tetroxide 9 B2u 265 219 -46 1.212
N2O3 Dinitrogen trioxide 9 A" 63 140 77 0.451
C3 carbon trimer 3 Πu 63 179 116 0.354
C3 carbon trimer 3 Πu 63 177 114 0.357
C3 carbon trimer 3 Πu 63 179 116 0.354
C3 carbon trimer 3 Πu 63 177 114 0.357
SF5Cl sulfur chloropentafluoride 5 B1 625 439 -186 1.425
SF5Cl sulfur chloropentafluoride 7 B2 505 295 -210 1.713
SF5Cl sulfur chloropentafluoride 11 E 397 231 -166 1.719
SiH- silicon monohydride anion 1 Σ 2175 1728 -447 1.258
SiH- silicon monohydride anion 1 Σ 2175 1728 -447 1.258
SiH- silicon monohydride anion 1 Σ 2175 1728 -447 1.258
SiH- silicon monohydride anion 1 Σ 2175 1728 -447 1.258
ZnH2 Zinc hydride 3 Πu 633 497 -136 1.274
H2OH2O water dimer 12 A" 88 -60 -148 -1.477
ClOO chloroperoxy radical 2 A' 414 298 -116 1.388
ClOO chloroperoxy radical 3 A' 201 123 -79 1.643
Cl3- trichloride anion 2 Σu 327 267 -60 1.226
H2OH2O water dimer 6 A' 311 446 135 0.698
H2OH2O water dimer 7 A' 143 224 81 0.637
H2OH2O water dimer 11 A" 108 166 58 0.649
H2POH Phosphinous acid 9 A" 375 244 -132 1.540
ZnCH3 Zinc monomethyl 6 E 315 592 277 0.532