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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 mPW1PW91/6-31G(2df,p)
Calculated values were scaled by 0.9547.

Species Name mode Symmetry Experiment Theory difference ratio
CH3COOH Acetic acid 18 A" 93 71 -22 1.303
CH3OH Methyl alcohol 12 A" 200 311 111 0.643
CH3OH Methyl alcohol 12 A" 200 309 109 0.646
CH3OH Methyl alcohol 12 A" 200 311 111 0.643
CH3OH Methyl alcohol 12 A" 200 309 109 0.646
CH3CONH2 Acetamide 20 A 259 168 -91 1.542
C3H4O2 β–Propiolactone 21 A" 113 177 64 0.638
C2H6O2S Dimethyl sulfone 20 B1 262 206 -56 1.269
CHONH2 formamide 12 A" 289 169 -120 1.711
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 229 -47 1.204
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 228 -48 1.209
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 229 -47 1.204
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 228 -48 1.209
CH3COCl Acetyl Chloride 15 A" 166 136 -30 1.224
CBr2F2 Methane, dibromodifluoro- 3 A1 140 337 197 0.415
C2F6 hexafluoroethane 4 A1u 68 55 -13 1.232
C3F8 perfluoropropane 13 A2 276 209 -67 1.323
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 523 -109 1.209
C6H4O2 parabenzoquinone 30 B3u 109 90 -19 1.206
C3H6O 2-Propen-1-ol 22 A 377 310 -68 1.219
C3H6O 2-Propen-1-ol 24 A 188 112 -77 1.686
C4H8O Furan, tetrahydro- 17 A 286 237 -49 1.205
C4H8O2 1,4-Dioxane 19 Au 288 236 -52 1.220
C5H8 Cyclopentene 18 A' 254 135 -119 1.878
C2H4O3 trioxolane124 21 B 193 157 -36 1.228
C5H12 Propane, 2,2-dimethyl- 12 T1 203 298 95 0.682
C4H6O2 2,3-Butanedione 9 Ag 614 506 -108 1.214
C4H6O2 2,3-Butanedione 13 Au 1111 909 -202 1.222
C4H6O2 2,3-Butanedione 21 Bg 240 101 -139 2.373
C6H4 Benzyne 24 B2 472 344 -128 1.374
C2H3NO3 Oxamic acid 3 A' 2600 3480 880 0.747
C2H3NO3 Oxamic acid 15 A' 328 256 -72 1.280
C2H3NO3 Oxamic acid 16 A" 984 816 -168 1.205
C2H3NO3 Oxamic acid 17 A" 815 661 -154 1.234
C2H3NO3 Oxamic acid 18 A" 745 618 -127 1.206
C2H3NO3 Oxamic acid 21 A" 162 70 -92 2.313
HCNO fulminic acid 5 Π 224 182 -42 1.232
Zn(CH3)2 dimethyl zinc 11 E' 134 100 -34 1.335
C5H8 1,4-Pentadiene 16 A 137 281 144 0.487
C5H8 1,4-Pentadiene 17 A 102 84 -18 1.212
COBr2 Carbonic dibromide 4 B1 757 524 -233 1.445
COBr2 Carbonic dibromide 6 B2 512 349 -163 1.469
C6H10 1,5-Hexadiene 14 Ag 351 251 -100 1.399
C6H10 1,5-Hexadiene 29 Bg 264 186 -78 1.416
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 185 -42 1.224
CH2D2 methane-d2 6 B1 3013 2255 -758 1.336
CH2D2 methane-d2 8 B2 2234 3045 811 0.734
NaOH sodium hydroxide 3 Π 300 127 -173 2.368
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 138 -32 1.235
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 346 -110 1.316
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 140 -31 1.217
CH3OCH2CN Methoxyacetonitrile 15 A' 243 176 -67 1.381
CH3OCH2CN Methoxyacetonitrile 24 A" 113 85 -28 1.330
CH3OO methylperoxy radical 12 A" 170 125 -45 1.362
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 148 -116 1.790
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 98 -260 3.644
CH3 Methyl radical 2 A2" 606 451 -156 1.346
CH3 Methyl radical 2 A2" 606 451 -156 1.346
CH3 Methyl radical 2 A2" 606 451 -156 1.346
CH3 Methyl radical 2 A2" 606 451 -156 1.346
CH2OH Hydroxymethyl radical 9 A 234 416 182 0.563
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 860 -276 1.321
C4H6 Methylenecyclopropane 17 B1 360 290 -70 1.240
C2Cl2+ dichloroacetylene cation 5 Πu 233 187 -46 1.248
BF3+ boron trifluoride cation 3 E' 1662 911 -751 1.824
BF3+ boron trifluoride cation 4 E' 411 -227 -638 -1.810
ZnCN Zinc monocyanide 3 Π 212 132 -80 1.606
GaF3 Gallium trifluoride 4 E' 192 110 -82 1.744
Li2O dilithium oxide 3 Πu 112 160 48 0.699
CaF2 Calcium difluoride 2 A1 120 92 -28 1.307
PCl5 Phosphorus pentachloride 2 A1' 370 279 -91 1.327
N2O3 Dinitrogen trioxide 9 A" 63 143 80 0.439
C3 carbon trimer 3 Πu 63 123 60 0.515
C3 carbon trimer 3 Πu 63 124 60 0.513
C3 carbon trimer 3 Πu 63 123 60 0.515
C3 carbon trimer 3 Πu 63 124 60 0.513
CaOH Calcium monohydroxide 2 Σ 353 616 263 0.573
CaOH Calcium monohydroxide 3 Π 609 332 -277 1.835
SiH- silicon monohydride anion 1 Σ 2175 1782 -393 1.220
SiH- silicon monohydride anion 1 Σ 2175 1782 -393 1.220
SiH- silicon monohydride anion 1 Σ 2175 1782 -393 1.220
SiH- silicon monohydride anion 1 Σ 2175 1782 -393 1.220
SF5Cl sulfur chloropentafluoride 5 B1 625 477 -148 1.310
SF5Cl sulfur chloropentafluoride 7 B2 505 320 -185 1.580
SF5Cl sulfur chloropentafluoride 11 E 397 253 -144 1.571
ZnH2 Zinc hydride 3 Πu 633 397 -236 1.594
ClOO chloroperoxy radical 2 A' 414 304 -109 1.360
ClOO chloroperoxy radical 3 A' 201 124 -77 1.622
GeH2 germylene 1 A1 1856 915 -941 2.028
GeH2 germylene 2 A1 916 1892 976 0.484
Mg2 Magnesium diatomic 1 Σg 51 88 37 0.578
Mg2 Magnesium diatomic 1 Σg 51 88 37 0.578
Mg2 Magnesium diatomic 1 Σg 51 88 37 0.578
Mg2 Magnesium diatomic 1 Σg 51 88 37 0.578
Cl3- trichloride anion 2 Σu 327 264 -63 1.237
ZnCH3 Zinc monomethyl 6 E 315 571 256 0.551
H2POH Phosphinous acid 9 A" 375 260 -116 1.446
H2OH2O water dimer 12 A" 88 48 -40 1.843
H2OH2O water dimer 11 A" 108 167 59 0.648
H2OH2O water dimer 8 A' 103 153 50 0.674
H2OH2O water dimer 7 A' 143 209 66 0.685