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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
CH3COOH Acetic acid 18 A" 93 74 -19 1.260
CH3CONH2 Acetamide 20 A 259 122 -136 2.116
CH3OH Methyl alcohol 12 A" 200 332 132 0.603
CH3OH Methyl alcohol 12 A" 200 331 131 0.603
CH3OH Methyl alcohol 12 A" 200 332 132 0.603
CH3OH Methyl alcohol 12 A" 200 331 131 0.603
CH3COCH3 Acetone 12 A2 77 12 -65 6.275
C2H6O2S Dimethyl sulfone 13 A2 326 268 -58 1.216
C2H6O2S Dimethyl sulfone 20 B1 262 209 -53 1.256
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
C5H8 Cyclopentene 18 A' 254 137 -117 1.849
C4H8O2 1,4-Dioxane 19 Au 288 240 -48 1.200
C6H4 Benzyne 24 B2 472 383 -89 1.232
C4H6O2 2,3-Butanedione 21 Bg 240 105 -135 2.284
C4H6O2 2,3-Butanedione 13 Au 1111 923 -188 1.204
C4H6O2 2,3-Butanedione 9 Ag 614 503 -111 1.220
C2H3NO3 Oxamic acid 3 A' 2600 3459 859 0.752
C3O2 Carbon suboxide 7 Πu 61 117 56 0.521
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
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
CH3SSCH3 Disulfide, dimethyl 13 A 117 96 -21 1.214
CH2D2 methane-d2 8 B2 2234 3043 809 0.734
CH3ONO Methyl nitrite 15 A" 186 122 -64 1.525
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 186 -41 1.218
C2F2 difluoroacetylene 4 Πg 270 208 -62 1.298
CH2D2 methane-d2 6 B1 3013 2254 -759 1.337
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
C2H5 Ethyl radical 9 A' 528 439 -89 1.204
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
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
C2Cl2 dichloroacetylene 4 Πg 333 277 -56 1.201
BF3+ boron trifluoride cation 4 E' 411 93 -318 4.423
BF3+ boron trifluoride cation 3 E' 1662 972 -689 1.709
MgF2 Magnesium fluoride 3 Πu 165 133 -32 1.240
C2Cl2+ dichloroacetylene cation 5 Πu 233 177 -56 1.313
SF4 Sulfur tetrafluoride 4 A1 228 183 -45 1.244
AsH3+ Arsine cation 2 A1 452 675 223 0.670
BrF5 bromine pentafluoride 6 B2 281 206 -75 1.361
ZnCN Zinc monocyanide 3 Π 212 56 -156 3.815
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
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
N2O3 Dinitrogen trioxide 9 A" 63 139 76 0.452
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
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
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
ClOO chloroperoxy radical 2 A' 414 325 -89 1.274
ClOO chloroperoxy radical 3 A' 201 116 -85 1.732
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
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