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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 0.9603.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 177 64 0.639
CH3CONH2 Acetamide 20 A 259 129 -130 2.006
CH3COOH Acetic acid 18 A" 93 76 -17 1.225
CH3OH Methyl alcohol 12 A" 200 331 131 0.605
CH3OH Methyl alcohol 12 A" 200 331 131 0.604
CH3OH Methyl alcohol 12 A" 200 331 131 0.605
CH3OH Methyl alcohol 12 A" 200 331 131 0.604
CH3COCH3 Acetone 12 A2 77 33 -44 2.306
C2H6O2S Dimethyl sulfone 13 A2 326 267 -59 1.219
C2H6O2S Dimethyl sulfone 20 B1 262 206 -56 1.273
CHONH2 formamide 12 A" 289 83 -206 3.487
CH3COCl Acetyl Chloride 15 A" 166 131 -35 1.265
CH3NO2 Methane, nitro- 11 A" 1583 3066 1483 0.516
CBr2F2 Methane, dibromodifluoro- 3 A1 140 312 172 0.448
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 523 -109 1.209
C2F6 hexafluoroethane 4 A1u 68 45 -23 1.511
CH3COOCH3 methyl acetate 27 A" 110 50 -60 2.200
C3F8 perfluoropropane 13 A2 276 210 -66 1.313
CH2BrCH2Br Ethane, 1,2-dibromo- 10 Au 118 98 -20 1.203
C3H6O 2-Propen-1-ol 24 A 188 113 -75 1.668
C4H8O2 1,4-Dioxane 19 Au 288 240 -48 1.201
C5H8 Cyclopentene 18 A' 254 134 -120 1.895
C2H3N3 1H-1,2,4-Triazole 18 A" 640 517 -123 1.238
C4H6O2 2,3-Butanedione 9 Ag 614 503 -111 1.220
C4H6O2 2,3-Butanedione 21 Bg 240 109 -131 2.199
NH2CN cyanamide 5 A' 408 585 177 0.697
C6H4 Benzyne 24 B2 472 390 -82 1.211
C5H12 Propane, 2,2-dimethyl- 12 T1 203 299 96 0.679
C2H3NO3 Oxamic acid 3 A' 2600 3453 853 0.753
C2H3NO3 Oxamic acid 15 A' 328 259 -69 1.265
C2H3NO3 Oxamic acid 16 A" 984 785 -199 1.253
C2H3NO3 Oxamic acid 17 A" 815 663 -152 1.230
C2H3NO3 Oxamic acid 18 A" 745 615 -130 1.212
C2H3NO3 Oxamic acid 21 A" 162 65 -97 2.498
C3O2 Carbon suboxide 7 Πu 61 124 63 0.491
C5H8 1,4-Pentadiene 16 A 137 288 151 0.475
C6H10 1,5-Hexadiene 14 Ag 351 257 -94 1.367
C6H10 1,5-Hexadiene 29 Bg 264 181 -83 1.459
COBr2 Carbonic dibromide 4 B1 757 495 -262 1.528
COBr2 Carbonic dibromide 6 B2 512 324 -188 1.582
CH3SSCH3 Disulfide, dimethyl 13 A 117 95 -22 1.236
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 187 -40 1.214
CH2D2 methane-d2 6 B1 3013 2249 -764 1.340
CH2D2 methane-d2 8 B2 2234 3037 803 0.736
C2F2 difluoroacetylene 4 Πg 270 194 -76 1.390
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 141 -29 1.202
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 210 66 0.684
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 210 66 0.684
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 346 -110 1.319
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 346 -110 1.319
C2H5 Ethyl radical 9 A' 528 439 -89 1.202
CH3OO methylperoxy radical 12 A" 170 134 -36 1.269
CH3 Methyl radical 2 A2" 606 435 -172 1.394
C4H9N Cyclobutylamine 21 A' 174 144 -30 1.209
CH2OH Hydroxymethyl radical 9 A 234 433 199 0.541
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 865 -271 1.313
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 150 -114 1.757
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 100 -258 3.568
OH- hydroxide anion 1 Σ 3738 3281 -457 1.139
C4H6 Methylenecyclopropane 17 B1 360 282 -78 1.278
C2Cl2 dichloroacetylene 4 Πg 333 277 -56 1.203
C2Cl2+ dichloroacetylene cation 5 Πu 233 177 -56 1.319
HClO4 perchloric acid 12 A" 191 151 -40 1.268
ClFO3 Perchloryl fluoride 6 E 405 332 -73 1.219
BF3+ boron trifluoride cation 3 E' 1662 974 -687 1.706
BF3+ boron trifluoride cation 4 E' 411 118 -293 3.469
MgF2 Magnesium fluoride 3 Πu 165 132 -33 1.254
SF4 Sulfur tetrafluoride 4 A1 228 181 -47 1.257
AsH3+ Arsine cation 2 A1 452 688 236 0.657
ZnCN Zinc monocyanide 3 Π 212 49 -163 4.288
BrF5 bromine pentafluoride 6 B2 281 203 -78 1.385
C3 carbon trimer 3 Πu 63 179 116 0.353
C3 carbon trimer 3 Πu 63 178 114 0.357
C3 carbon trimer 3 Πu 63 179 116 0.353
C3 carbon trimer 3 Πu 63 178 114 0.357
CaOH Calcium monohydroxide 2 Σ 353 601 248 0.587
CaOH Calcium monohydroxide 3 Π 609 329 -280 1.851
Fe(CO)5 Iron pentacarbonyl 5 A2' 383 300 -83 1.275
Fe(CO)5 Iron pentacarbonyl 13 E' 474 377 -98 1.259
Fe(CO)5 Iron pentacarbonyl 15 E' 74 33 -41 2.246
PCl5 Phosphorus pentachloride 2 A1' 370 257 -113 1.441
N2O4 Dinitrogen tetroxide 9 B2u 265 220 -45 1.206
SiH- silicon monohydride anion 1 Σ 2175 1731 -444 1.256
SiH- silicon monohydride anion 1 Σ 2175 1731 -444 1.256
SiH- silicon monohydride anion 1 Σ 2175 1731 -444 1.256
SiH- silicon monohydride anion 1 Σ 2175 1731 -444 1.256
Cu2 Copper dimer 1 Σg 265 387 122 0.684
ZnH2 Zinc hydride 3 Πu 633 499 -133 1.267
Cl3- trichloride anion 2 Σu 327 266 -61 1.229
H2POH Phosphinous acid 9 A" 375 241 -134 1.556
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
ZnCH3 Zinc monomethyl 6 E 315 593 278 0.531
ClOO chloroperoxy radical 2 A' 414 300 -114 1.378
ClOO chloroperoxy radical 3 A' 201 122 -80 1.657
SF5Cl sulfur chloropentafluoride 5 B1 625 439 -186 1.425
SF5Cl sulfur chloropentafluoride 7 B2 505 295 -210 1.712
SF5Cl sulfur chloropentafluoride 11 E 397 231 -166 1.720
H2OH2O water dimer 6 A' 311 445 134 0.698
H2OH2O water dimer 7 A' 143 224 81 0.639
H2OH2O water dimer 11 A" 108 164 56 0.659
H2OH2O water dimer 12 A" 88 -65 -153 -1.348