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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 BLYP/6-31G(2df,p)
Calculated values were scaled by 0.9945.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 182 69 0.619
CH3OH Methyl alcohol 12 A" 200 328 128 0.611
CH3OH Methyl alcohol 12 A" 200 322 122 0.622
CH3OH Methyl alcohol 12 A" 200 328 128 0.611
CH3OH Methyl alcohol 12 A" 200 322 122 0.622
CH3COOH Acetic acid 18 A" 93 61 -32 1.519
C2H2 Acetylene 4 Πg 612 442 -170 1.384
C2H6O2S Dimethyl sulfone 13 A2 326 267 -59 1.220
C2H6O2S Dimethyl sulfone 20 B1 262 197 -65 1.330
CHONH2 formamide 12 A" 289 87 -202 3.336
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 227 -49 1.214
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 227 -49 1.214
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 227 -49 1.214
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 227 -49 1.214
CH3COCl Acetyl Chloride 15 A" 166 131 -35 1.272
CBr2F2 Methane, dibromodifluoro- 3 A1 140 311 171 0.450
C2F6 hexafluoroethane 4 A1u 68 51 -17 1.323
C3F8 perfluoropropane 13 A2 276 210 -66 1.315
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 521 -111 1.212
CH2BrCH2Br Ethane, 1,2-dibromo- 10 Au 118 98 -20 1.203
CH3OCHO methyl formate 18 A" 130 93 -37 1.397
C3H6O 2-Propen-1-ol 24 A 188 113 -75 1.670
C4H8O Furan, tetrahydro- 17 A 286 236 -50 1.214
C4H8O2 1,4-Dioxane 19 Au 288 235 -53 1.227
C5H8 Cyclopentene 18 A' 254 123 -131 2.062
C2H3N3 1H-1,2,4-Triazole 18 A" 640 516 -124 1.241
C2H4O3 trioxolane124 21 B 193 153 -40 1.261
C2H2N4 sym-tetrazine 18 B3u 254 151 -103 1.684
NH2CN cyanamide 5 A' 408 598 190 0.682
C6H4 Benzyne 24 B2 472 367 -105 1.286
C4H2 Diacetylene 8 Πu 630 516 -114 1.221
C4H6O2 2,3-Butanedione 21 Bg 240 99 -141 2.424
C4H6O2 2,3-Butanedione 13 Au 1111 918 -193 1.211
C4H6O2 2,3-Butanedione 9 Ag 614 496 -118 1.237
C5H12 Propane, 2,2-dimethyl- 12 T1 203 300 97 0.677
C2H3NO3 Oxamic acid 3 A' 2600 3472 872 0.749
C2H3NO3 Oxamic acid 15 A' 328 257 -71 1.276
C2H3NO3 Oxamic acid 16 A" 984 793 -191 1.241
C2H3NO3 Oxamic acid 17 A" 815 664 -151 1.227
C2H3NO3 Oxamic acid 21 A" 162 67 -95 2.406
C3O2 Carbon suboxide 7 Πu 61 90 29 0.679
Zn(CH3)2 dimethyl zinc 11 E' 134 91 -43 1.474
C6H10 1,5-Hexadiene 14 Ag 351 254 -97 1.380
C6H10 1,5-Hexadiene 29 Bg 264 182 -82 1.449
C5H8 1,4-Pentadiene 16 A 137 289 152 0.475
COBr2 Carbonic dibromide 4 B1 757 506 -251 1.495
COBr2 Carbonic dibromide 6 B2 512 323 -189 1.583
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 185 -42 1.226
CH2D2 methane-d2 6 B1 3013 2264 -749 1.331
CH2D2 methane-d2 8 B2 2234 3059 825 0.730
C2F2 difluoroacetylene 4 Πg 270 36 -234 7.484
CH3ONO Methyl nitrite 15 A" 186 132 -54 1.405
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 208 64 0.693
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 350 -106 1.303
CH3OCH2CN Methoxyacetonitrile 15 A' 243 176 -67 1.378
CH3OCH2CN Methoxyacetonitrile 24 A" 113 85 -28 1.334
CH3OO methylperoxy radical 12 A" 170 123 -47 1.383
CH3 Methyl radical 2 A2" 606 469 -138 1.293
CH3 Methyl radical 2 A2" 606 469 -138 1.293
CH3 Methyl radical 2 A2" 606 469 -138 1.293
CH3 Methyl radical 2 A2" 606 469 -138 1.293
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 157 -107 1.680
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 106 -252 3.391
CH2OH Hydroxymethyl radical 9 A 234 444 210 0.527
C4H9N Cyclobutylamine 21 A' 174 130 -44 1.341
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 865 -271 1.313
OH- hydroxide anion 1 Σ 3738 3319 -419 1.126
C2Cl2+ dichloroacetylene cation 5 Πu 233 182 -51 1.283
C4H6 Methylenecyclopropane 17 B1 360 287 -73 1.257
HClO4 perchloric acid 12 A" 191 133 -58 1.438
BF3+ boron trifluoride cation 3 E' 1662 1133 -528 1.466
BF3+ boron trifluoride cation 4 E' 411 267 -144 1.538
SOCl2 thionyl chloride 4 A' 194 157 -37 1.233
GaF3 Gallium trifluoride 4 E' 192 106 -86 1.806
ClF3 Chlorine trifluoride 6 B2 442 354 -88 1.249
Cl2O Dichlorine monoxide 3 B2 686 536 -150 1.279
SO2Cl2 Sulfuryl chloride 3 A1 408 338 -70 1.206
SO2Cl2 Sulfuryl chloride 4 A1 218 178 -40 1.222
SO2Cl2 Sulfuryl chloride 7 B1 388 322 -66 1.204
BrF5 bromine pentafluoride 6 B2 281 208 -73 1.348
CaF2 Calcium difluoride 2 A1 120 95 -25 1.261
ClF3 Chlorine trifluoride 3 A1 328 250 -78 1.310
PCl5 Phosphorus pentachloride 2 A1' 370 254 -116 1.456
PCl5 Phosphorus pentachloride 7 E' 100 78 -22 1.281
ZnCN Zinc monocyanide 3 Π 212 105 -107 2.015
NCl3 nitrogen trichloride 3 E 642 505 -137 1.272
N2O3 Dinitrogen trioxide 9 A" 63 140 77 0.450
Li2O dilithium oxide 3 Πu 112 160 48 0.697
C3 carbon trimer 3 Πu 63 162 98 0.392
C3 carbon trimer 3 Πu 63 162 99 0.391
C3 carbon trimer 3 Πu 63 162 98 0.392
C3 carbon trimer 3 Πu 63 162 99 0.391
CaOH Calcium monohydroxide 2 Σ 353 618 265 0.571
CaOH Calcium monohydroxide 3 Π 609 310 -299 1.962
C4 Carbon tetramer 4 Πg 323 259 -64 1.247
Cu2 Copper dimer 1 Σg 265 427 162 0.620
N2O4 Dinitrogen tetroxide 9 B2u 265 173 -92 1.533
SiH- silicon monohydride anion 1 Σ 2175 1753 -422 1.241
SiH- silicon monohydride anion 1 Σ 2175 1753 -422 1.241
SiH- silicon monohydride anion 1 Σ 2175 1753 -422 1.241
SiH- silicon monohydride anion 1 Σ 2175 1753 -422 1.241
ZnH2 Zinc hydride 3 Πu 633 355 -278 1.782
SF5Cl sulfur chloropentafluoride 5 B1 625 451 -174 1.387
SF5Cl sulfur chloropentafluoride 7 B2 505 299 -206 1.690
SF5Cl sulfur chloropentafluoride 11 E 397 235 -162 1.691
ClONO2 Chlorine nitrate 7 A' 273 215 -59 1.273
Cl3- trichloride anion 2 Σu 327 270 -57 1.212
GeH2 germylene 1 A1 1856 923 -933 2.010
GeH2 germylene 2 A1 916 1822 906 0.503
H2POH Phosphinous acid 9 A" 375 237 -138 1.581
ZnCH3 Zinc monomethyl 6 E 315 579 264 0.544
H2OH2O water dimer 7 A' 143 213 70 0.670
H2OH2O water dimer 8 A' 103 150 47 0.684
H2OH2O water dimer 11 A" 108 174 66 0.622
H2OH2O water dimer 12 A" 88 -97 -185 -0.912