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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 LSDA/6-31+G**
Calculated values were scaled by 0.9839.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 183 70 0.619
CH3COOH Acetic acid 18 A" 93 62 -31 1.503
CH3OH Methyl alcohol 12 A" 200 314 114 0.637
CH3OH Methyl alcohol 12 A" 200 313 113 0.639
CH3OH Methyl alcohol 12 A" 200 314 114 0.637
CH3OH Methyl alcohol 12 A" 200 313 113 0.639
C2H6O2S Dimethyl sulfone 20 B1 262 216 -46 1.215
C2H6O2S Dimethyl sulfone 13 A2 326 270 -56 1.207
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 315 101 0.680
CH3COCl Acetyl Chloride 15 A" 166 124 -42 1.335
CBr2F2 Methane, dibromodifluoro- 3 A1 140 337 197 0.416
C2F6 hexafluoroethane 4 A1u 68 48 -20 1.404
C3F8 perfluoropropane 13 A2 276 205 -71 1.343
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 62 -13 1.209
C6H4O2 parabenzoquinone 30 B3u 109 90 -19 1.208
CH3OCHO methyl formate 18 A" 130 105 -25 1.242
C3H6O 2-Propen-1-ol 22 A 377 309 -68 1.219
C3H6O 2-Propen-1-ol 24 A 188 116 -72 1.616
C3H2N2 Malononitrile 6 A1 167 136 -31 1.227
C5H8 Cyclopentene 18 A' 254 172 -82 1.476
C4H4N2 Pyridazine 13 A2 421 335 -86 1.256
C2H2N4 sym-tetrazine 5 Au 335 261 -74 1.283
NH2CN cyanamide 6 A' 487 348 -139 1.398
C2H2N4 sym-tetrazine 18 B3u 254 61 -193 4.171
C4H6O2 2,3-Butanedione 21 Bg 240 76 -164 3.151
C4H6O2 2,3-Butanedione 9 Ag 614 505 -109 1.215
C4H6O2 2,3-Butanedione 13 Au 1111 875 -236 1.270
C4H6O2 2,3-Butanedione 16 Au 48 36 -12 1.352
C3O2 Carbon suboxide 7 Πu 61 174 113 0.350
C5H12 Propane, 2,2-dimethyl- 12 T1 203 325 122 0.626
C2H3NO3 Oxamic acid 3 A' 2600 3424 824 0.759
C2H3NO3 Oxamic acid 15 A' 328 256 -72 1.281
C2H3NO3 Oxamic acid 16 A" 984 793 -191 1.241
C2H3NO3 Oxamic acid 17 A" 815 670 -145 1.216
C2H3NO3 Oxamic acid 21 A" 162 80 -82 2.013
HCNO fulminic acid 5 Π 224 169 -55 1.328
COBr2 Carbonic dibromide 4 B1 757 528 -229 1.433
COBr2 Carbonic dibromide 6 B2 512 347 -165 1.474
C5H8 1,4-Pentadiene 16 A 137 287 150 0.478
C6H10 1,5-Hexadiene 14 Ag 351 264 -87 1.327
C6H10 1,5-Hexadiene 29 Bg 264 207 -57 1.273
CH2D2 methane-d2 6 B1 3013 2275 -738 1.324
CH2D2 methane-d2 8 B2 2234 3073 839 0.727
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 182 -45 1.245
CH3SSCH3 Disulfide, dimethyl 13 A 117 83 -34 1.402
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 136 -34 1.245
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 214 70 0.672
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 214 70 0.672
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 214 70 0.672
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 214 70 0.672
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 341 -115 1.336
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 341 -115 1.337
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 341 -115 1.336
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 341 -115 1.337
CH3OO methylperoxy radical 12 A" 170 129 -41 1.321
CH2OH Hydroxymethyl radical 9 A 234 361 127 0.648
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 875 -261 1.299
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 159 -105 1.656
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 107 -251 3.350
C4H6 Methylenecyclopropane 17 B1 360 283 -77 1.274
C2Cl2 dichloroacetylene 4 Πg 333 232 -101 1.437
C2Cl2+ dichloroacetylene cation 5 Πu 233 178 -55 1.307
HClO4 perchloric acid 12 A" 191 157 -34 1.213
SOCl2 thionyl chloride 4 A' 194 162 -32 1.200
SF4 Sulfur tetrafluoride 4 A1 228 181 -47 1.262
ClFO3 Perchloryl fluoride 6 E 405 329 -76 1.230
BrF3 Bromine trifluoride 3 A1 242 200 -42 1.207
F2SO Thionyl Fluoride 4 A' 378 311 -67 1.214
ClF3 Chlorine trifluoride 3 A1 328 265 -63 1.236
ClF3 Chlorine trifluoride 6 B2 442 367 -75 1.203
BF3+ boron trifluoride cation 4 E' 411 261 -150 1.575
BF3+ boron trifluoride cation 3 E' 1662 1210 -451 1.373
BrF5 bromine pentafluoride 3 A1 369 299 -70 1.234
BrF5 bromine pentafluoride 6 B2 281 187 -94 1.500
Li2O dilithium oxide 3 Πu 112 79 -32 1.410
PCl5 Phosphorus pentachloride 2 A1' 370 276 -94 1.340
N2O4 Dinitrogen tetroxide 9 B2u 265 212 -53 1.250
N2O3 Dinitrogen trioxide 9 A" 63 139 76 0.454
SiH- silicon monohydride anion 1 Σ 2175 1772 -403 1.228
SiH- silicon monohydride anion 1 Σ 2175 1772 -403 1.228
SiH- silicon monohydride anion 1 Σ 2175 1772 -403 1.228
SiH- silicon monohydride anion 1 Σ 2175 1772 -403 1.228
SF5Cl sulfur chloropentafluoride 5 B1 625 437 -188 1.429
SF5Cl sulfur chloropentafluoride 7 B2 505 293 -212 1.721
SF5Cl sulfur chloropentafluoride 11 E 397 233 -164 1.707
H3O+ hydronium 2 A1 954 675 -280 1.414
C3 carbon trimer 3 Πu 63 134 71 0.472
C3 carbon trimer 3 Πu 63 134 71 0.472
C3 carbon trimer 3 Πu 63 134 71 0.472
C3 carbon trimer 3 Πu 63 134 71 0.472
ClOO chloroperoxy radical 3 A' 201 316 115 0.637
Mg2 Magnesium diatomic 1 Σg 51 119 68 0.430
Mg2 Magnesium diatomic 1 Σg 51 119 68 0.430
Mg2 Magnesium diatomic 1 Σg 51 119 68 0.430
Mg2 Magnesium diatomic 1 Σg 51 119 68 0.430
ZnCH3 Zinc monomethyl 6 E 315 578 263 0.545
GeH2 germylene 2 A1 916 1965 1049 0.466
GeH2 germylene 1 A1 1856 896 -960 2.071
BrONO Bromine nitrite 3 A' 587 1741 1154 0.337
BrONO Bromine nitrite 4 A' 391 877 486 0.446
H2POH Phosphinous acid 9 A" 375 253 -123 1.486
H2OH2O water dimer 12 A" 88 160 72 0.550
H2OH2O water dimer 11 A" 108 198 90 0.544
H2OH2O water dimer 10 A" 523 818 295 0.639
H2OH2O water dimer 8 A' 103 205 102 0.502
H2OH2O water dimer 7 A' 143 269 126 0.531
H2OH2O water dimer 6 A' 311 466 155 0.668
B2H6 Diborane 14 B2u 368 268 -100 1.372