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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 B3PW91/6-31G*
Calculated values were scaled by 0.9567.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 176 63 0.644
CH3CONH2 Acetamide 20 A 259 122 -136 2.116
CH3COOH Acetic acid 18 A" 93 74 -19 1.260
CH3COCH3 Acetone 12 A2 77 12 -65 6.275
CH3OH Methyl alcohol 12 A" 200 332 132 0.603
CH3OH Methyl alcohol 12 A" 200 331 131 0.603
C2H6O2S Dimethyl sulfone 13 A2 326 268 -58 1.216
C2H6O2S Dimethyl sulfone 20 B1 262 209 -53 1.256
CH3OH Methyl alcohol 12 A" 200 332 132 0.603
CH3OH Methyl alcohol 12 A" 200 331 131 0.603
CHONH2 formamide 12 A" 289 144 -144 2.001
CH3COCl Acetyl Chloride 15 A" 166 130 -36 1.279
CBr2F2 Methane, dibromodifluoro- 3 A1 140 320 180 0.438
C2F6 hexafluoroethane 4 A1u 68 48 -20 1.408
C3F8 perfluoropropane 13 A2 276 208 -68 1.328
CHOCH(CH3)CH3 Propanal, 2-methyl- 16 A' 632 523 -109 1.209
CH3COOCH3 methyl acetate 27 A" 110 45 -65 2.436
C3H6O 2-Propen-1-ol 22 A 377 313 -64 1.206
C3H6O 2-Propen-1-ol 24 A 188 112 -76 1.678
C4H8O2 1,4-Dioxane 19 Au 288 240 -48 1.200
C5H8 Cyclopentene 18 A' 254 137 -117 1.849
C4H6O2 2,3-Butanedione 13 Au 1111 923 -188 1.204
C4H6O2 2,3-Butanedione 21 Bg 240 105 -135 2.284
C6H4 Benzyne 24 B2 472 383 -89 1.232
C4H6O2 2,3-Butanedione 9 Ag 614 503 -111 1.220
C2H3NO3 Oxamic acid 15 A' 328 256 -72 1.283
C2H3NO3 Oxamic acid 16 A" 984 789 -195 1.248
C2H3NO3 Oxamic acid 17 A" 815 664 -151 1.228
C2H3NO3 Oxamic acid 18 A" 745 616 -129 1.210
C2H3NO3 Oxamic acid 21 A" 162 66 -96 2.443
C2H3NO3 Oxamic acid 3 A' 2600 3459 859 0.752
C3O2 Carbon suboxide 7 Πu 61 117 56 0.521
C5H8 1,4-Pentadiene 16 A 137 285 148 0.481
C5H8 1,4-Pentadiene 17 A 102 85 -17 1.202
C6H10 1,5-Hexadiene 14 Ag 351 254 -97 1.383
C6H10 1,5-Hexadiene 29 Bg 264 184 -80 1.434
COBr2 Carbonic dibromide 4 B1 757 503 -254 1.505
COBr2 Carbonic dibromide 6 B2 512 331 -181 1.546
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 186 -41 1.218
CH3ONO Methyl nitrite 15 A" 186 122 -64 1.525
CH3SSCH3 Disulfide, dimethyl 13 A 117 96 -21 1.214
CH2D2 methane-d2 6 B1 3013 2254 -759 1.337
CH2D2 methane-d2 8 B2 2234 3043 809 0.734
C2F2 difluoroacetylene 4 Πg 270 208 -62 1.298
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 139 -31 1.222
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 207 63 0.694
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 207 63 0.695
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 207 63 0.694
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 207 63 0.695
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 342 -114 1.331
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 343 -113 1.331
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 342 -114 1.331
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 343 -113 1.331
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 142 -29 1.205
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 142 -29 1.207
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 142 -29 1.205
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 142 -29 1.207
CH3OO methylperoxy radical 12 A" 170 136 -34 1.248
CH3 Methyl radical 2 A2" 606 438 -169 1.386
CH3 Methyl radical 2 A2" 606 438 -169 1.386
CH3 Methyl radical 2 A2" 606 438 -169 1.386
CH3 Methyl radical 2 A2" 606 438 -169 1.386
C2H5 Ethyl radical 9 A' 528 439 -89 1.204
CH2OH Hydroxymethyl radical 9 A 234 427 193 0.548
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 866 -270 1.312
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 147 -117 1.790
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 99 -259 3.619
OH- hydroxide anion 1 Σ 3738 3336 -403 1.121
C4H6 Methylenecyclopropane 17 B1 360 281 -79 1.282
BF3+ boron trifluoride cation 4 E' 411 93 -318 4.423
BF3+ boron trifluoride cation 3 E' 1662 972 -689 1.709
C2Cl2+ dichloroacetylene cation 5 Πu 233 177 -56 1.313
BrF5 bromine pentafluoride 6 B2 281 206 -75 1.361
C2Cl2 dichloroacetylene 4 Πg 333 277 -56 1.201
MgF2 Magnesium fluoride 3 Πu 165 133 -32 1.240
SF4 Sulfur tetrafluoride 4 A1 228 183 -45 1.244
AsH3+ Arsine cation 2 A1 452 675 223 0.670
N2O3 Dinitrogen trioxide 9 A" 63 139 76 0.452
ZnCN Zinc monocyanide 3 Π 212 56 -156 3.815
C3 carbon trimer 3 Πu 63 144 80 0.441
C3 carbon trimer 3 Πu 63 145 81 0.438
C3 carbon trimer 3 Πu 63 144 80 0.441
C3 carbon trimer 3 Πu 63 145 81 0.438
PCl5 Phosphorus pentachloride 2 A1' 370 266 -104 1.393
NO3 Nitrogen trioxide 3 E' 1492 1151 -341 1.296
NO3 Nitrogen trioxide 4 E' 360 227 -133 1.587
CaOH Calcium monohydroxide 2 Σ 353 599 246 0.589
CaOH Calcium monohydroxide 3 Π 609 338 -271 1.799
Cu2 Copper dimer 1 Σg 265 387 122 0.684
SF5Cl sulfur chloropentafluoride 5 B1 625 443 -182 1.409
SF5Cl sulfur chloropentafluoride 7 B2 505 299 -206 1.687
SF5Cl sulfur chloropentafluoride 11 E 397 235 -162 1.687
ZnH2 Zinc hydride 3 Πu 633 492 -141 1.286
SiH- silicon monohydride anion 1 Σ 2175 1742 -433 1.249
SiH- silicon monohydride anion 1 Σ 2175 1742 -433 1.248
SiH- silicon monohydride anion 1 Σ 2175 1742 -433 1.249
SiH- silicon monohydride anion 1 Σ 2175 1742 -433 1.248
ClOO chloroperoxy radical 3 A' 201 116 -85 1.732
H2OH2O water dimer 7 A' 143 218 75 0.657
H2OH2O water dimer 8 A' 103 148 45 0.696
H2OH2O water dimer 11 A" 108 170 62 0.637
H2OH2O water dimer 12 A" 88 71 -17 1.241
H2POH Phosphinous acid 9 A" 375 250 -125 1.501
Mg2 Magnesium diatomic 1 Σg 51 83 32 0.613
Mg2 Magnesium diatomic 1 Σg 51 83 32 0.613
Mg2 Magnesium diatomic 1 Σg 51 83 32 0.613
Mg2 Magnesium diatomic 1 Σg 51 83 32 0.613
ZnCH3 Zinc monomethyl 6 E 315 596 281 0.529
ClOO chloroperoxy radical 2 A' 414 325 -89 1.274
Cl3- trichloride anion 2 Σu 327 270 -57 1.213
GeH2 germylene 1 A1 1856 906 -950 2.049
GeH2 germylene 2 A1 916 1744 828 0.525