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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 PBEPBE/6-31G(2df,p)
Calculated values were scaled by 0.9897.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 181 68 0.625
CH3OH Methyl alcohol 12 A" 200 322 122 0.620
CH3OH Methyl alcohol 12 A" 200 321 121 0.624
CH3OH Methyl alcohol 12 A" 200 322 122 0.620
CH3OH Methyl alcohol 12 A" 200 321 121 0.624
CH3COOH Acetic acid 18 A" 93 58 -35 1.594
C2H6O2S Dimethyl sulfone 20 B1 262 200 -62 1.311
CH3CONH2 Acetamide 20 A 259 209 -50 1.241
C2H6O2S Dimethyl sulfone 13 A2 326 268 -58 1.217
CH3COCH3 Acetone 12 A2 77 49 -28 1.583
C2H2 Acetylene 4 Πg 612 480 -132 1.275
CHONH2 formamide 12 A" 289 124 -164 2.323
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 230 -46 1.201
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 229 -47 1.204
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 230 -46 1.201
CH3CHClCH3 Propane, 2-chloro- 27 A" 276 229 -47 1.204
CH3COCl Acetyl Chloride 15 A" 166 130 -36 1.277
CBr2F2 Methane, dibromodifluoro- 3 A1 140 327 187 0.428
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 523 -109 1.207
C2F6 hexafluoroethane 4 A1u 68 50 -18 1.358
C3F8 perfluoropropane 13 A2 276 206 -70 1.343
C3H6O 2-Propen-1-ol 22 A 377 309 -68 1.219
C3H6O 2-Propen-1-ol 24 A 188 113 -75 1.659
CH3OCHO methyl formate 18 A" 130 93 -37 1.394
C4H8O2 1,4-Dioxane 19 Au 288 239 -49 1.205
C5H8 Cyclopentene 18 A' 254 134 -120 1.899
C2H4O3 trioxolane124 21 B 193 154 -39 1.254
C4H4N2 Pyridazine 13 A2 421 343 -78 1.226
C2H2N4 sym-tetrazine 18 B3u 254 103 -151 2.472
NH2CN cyanamide 5 A' 408 590 182 0.692
C4H6O2 2,3-Butanedione 9 Ag 614 498 -116 1.232
C4H6O2 2,3-Butanedione 13 Au 1111 896 -215 1.241
C4H6O2 2,3-Butanedione 21 Bg 240 91 -149 2.628
C2H3NO3 Oxamic acid 21 A" 162 71 -91 2.277
C2H3NO3 Oxamic acid 17 A" 815 671 -144 1.214
C2H3NO3 Oxamic acid 16 A" 984 797 -187 1.234
C2H3NO3 Oxamic acid 15 A' 328 254 -74 1.289
C2H3NO3 Oxamic acid 3 A' 2600 3478 878 0.747
C5H12 Propane, 2,2-dimethyl- 12 T1 203 305 102 0.666
C6H4 Benzyne 24 B2 472 364 -108 1.298
C3H6O Oxetane 12 A2 986 803 -183 1.229
C3H6O Oxetane 18 B1 90 42 -48 2.142
C3H6O Oxetane 23 B2 1228 1011 -217 1.215
C3O2 Carbon suboxide 7 Πu 61 88 27 0.692
Zn(CH3)2 dimethyl zinc 11 E' 134 96 -38 1.395
C6H10 1,5-Hexadiene 14 Ag 351 253 -98 1.387
C5H8 1,4-Pentadiene 16 A 137 284 147 0.482
C5H8 1,4-Pentadiene 17 A 102 84 -18 1.209
C6H10 1,5-Hexadiene 29 Bg 264 192 -72 1.378
COBr2 Carbonic dibromide 4 B1 757 516 -241 1.466
COBr2 Carbonic dibromide 6 B2 512 337 -175 1.518
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 184 -43 1.234
CH3ONO Methyl nitrite 15 A" 186 142 -44 1.309
CH2D2 methane-d2 6 B1 3013 2277 -736 1.323
CH2D2 methane-d2 8 B2 2234 3076 842 0.726
C2F2 difluoroacetylene 4 Πg 270 166 -104 1.631
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 139 -31 1.221
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 206 62 0.698
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 344 -112 1.324
CH3OCH2CN Methoxyacetonitrile 15 A' 243 175 -68 1.390
CH3OCH2CN Methoxyacetonitrile 24 A" 113 87 -26 1.302
CH3OO methylperoxy radical 12 A" 170 124 -46 1.374
CH3 Methyl radical 2 A2" 606 468 -138 1.295
CH3 Methyl radical 2 A2" 606 468 -138 1.295
CH3 Methyl radical 2 A2" 606 468 -138 1.295
CH3 Methyl radical 2 A2" 606 468 -138 1.295
CH2OH Hydroxymethyl radical 9 A 234 437 203 0.535
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 867 -269 1.311
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 158 -106 1.675
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 105 -253 3.421
C3H3 Propargyl radical 7 B1 490 408 -82 1.200
C4H6 Methylenecyclopropane 17 B1 360 284 -76 1.269
HClO4 perchloric acid 12 A" 191 134 -57 1.423
C2Cl2+ dichloroacetylene cation 5 Πu 233 184 -49 1.265
BF3+ boron trifluoride cation 4 E' 411 260 -151 1.582
BF3+ boron trifluoride cation 3 E' 1662 1143 -519 1.454
GaF3 Gallium trifluoride 4 E' 192 102 -90 1.877
ZnCN Zinc monocyanide 3 Π 212 104 -108 2.042
PCl5 Phosphorus pentachloride 7 E' 100 81 -19 1.234
BrF5 bromine pentafluoride 6 B2 281 218 -63 1.287
CaF2 Calcium difluoride 2 A1 120 93 -27 1.284
ClF3 Chlorine trifluoride 3 A1 328 271 -57 1.210
N2O4 Dinitrogen tetroxide 9 B2u 265 190 -75 1.396
N2O3 Dinitrogen trioxide 9 A" 63 143 80 0.441
PCl5 Phosphorus pentachloride 2 A1' 370 272 -98 1.360
CaOH Calcium monohydroxide 2 Σ 353 623 270 0.567
CaOH Calcium monohydroxide 3 Π 609 312 -297 1.952
Cu2 Copper dimer 1 Σg 265 429 164 0.617
C3 carbon trimer 3 Πu 63 97 33 0.655
C3 carbon trimer 3 Πu 63 97 33 0.655
C3 carbon trimer 3 Πu 63 97 33 0.655
C3 carbon trimer 3 Πu 63 97 33 0.655
C4 Carbon tetramer 4 Πg 323 196 -127 1.645
ZnH2 Zinc hydride 3 Πu 633 349 -284 1.813
SF5Cl sulfur chloropentafluoride 11 E 397 242 -155 1.639
SiH- silicon monohydride anion 1 Σ 2175 1772 -403 1.227
SiH- silicon monohydride anion 1 Σ 2175 1772 -403 1.227
SiH- silicon monohydride anion 1 Σ 2175 1772 -403 1.227
SiH- silicon monohydride anion 1 Σ 2175 1772 -403 1.227
SF5Cl sulfur chloropentafluoride 5 B1 625 459 -166 1.363
SF5Cl sulfur chloropentafluoride 7 B2 505 305 -200 1.653
ClONO2 Chlorine nitrate 7 A' 273 227 -47 1.207
ClOO chloroperoxy radical 3 A' 201 294 92 0.686
Mg2 Magnesium diatomic 1 Σg 51 107 56 0.477
Mg2 Magnesium diatomic 1 Σg 51 107 56 0.477
Mg2 Magnesium diatomic 1 Σg 51 107 56 0.477
Mg2 Magnesium diatomic 1 Σg 51 107 56 0.477
GeH2 germylene 1 A1 1856 913 -943 2.033
GeH2 germylene 2 A1 916 1852 936 0.495
H2OH2O water dimer 6 A' 311 445 134 0.699
H2OH2O water dimer 7 A' 143 223 80 0.640
H2OH2O water dimer 8 A' 103 150 47 0.686
H2OH2O water dimer 11 A" 108 177 69 0.610
B2H6 Diborane 14 B2u 368 300 -68 1.228
H2OH2O water dimer 12 A" 88 -104 -192 -0.845
H2POH Phosphinous acid 9 A" 375 243 -132 1.542
ZnCH3 Zinc monomethyl 6 E 315 575 260 0.548