return to home page

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/6-311G**
Calculated values were scaled by 0.9877.

Species Name mode Symmetry Experiment Theory difference ratio
CH3COOH Acetic acid 18 A" 93 75 -18 1.236
CH3OH Methyl alcohol 12 A" 200 334 134 0.600
CH3OH Methyl alcohol 12 A" 200 332 132 0.602
CH3OH Methyl alcohol 12 A" 200 334 134 0.600
CH3OH Methyl alcohol 12 A" 200 332 132 0.602
C3H4O2 β–Propiolactone 21 A" 113 184 71 0.614
C2H6O2S Dimethyl sulfone 20 B1 262 212 -50 1.235
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 320 106 0.669
CH3COCl Acetyl Chloride 15 A" 166 136 -30 1.223
C3F8 perfluoropropane 13 A2 276 206 -70 1.337
C2F6 hexafluoroethane 4 A1u 68 43 -25 1.589
CBr2F2 Methane, dibromodifluoro- 3 A1 140 334 194 0.420
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 60 -15 1.252
C6H4O2 parabenzoquinone 30 B3u 109 90 -19 1.208
CH3OCHO methyl formate 18 A" 130 86 -44 1.516
C3H6O 2-Propen-1-ol 22 A 377 309 -68 1.221
C3H6O 2-Propen-1-ol 24 A 188 121 -67 1.558
C5H8 Cyclopentene 18 A' 254 168 -86 1.512
C4H4N2 Pyridazine 13 A2 421 337 -84 1.249
C2H2N4 sym-tetrazine 5 Au 335 262 -73 1.278
C2H2N4 sym-tetrazine 18 B3u 254 -27 -281 -9.512
C4H6O2 2,3-Butanedione 9 Ag 614 511 -103 1.201
C4H6O2 2,3-Butanedione 13 Au 1111 876 -235 1.268
C4H6O2 2,3-Butanedione 16 Au 48 -34 -82 -1.409
C4H6O2 2,3-Butanedione 21 Bg 240 49 -191 4.862
C2H3NO3 Oxamic acid 15 A' 328 259 -69 1.268
C2H3NO3 Oxamic acid 16 A" 984 814 -170 1.209
C2H3NO3 Oxamic acid 21 A" 162 87 -75 1.865
C5H12 Propane, 2,2-dimethyl- 12 T1 203 325 122 0.625
C2H3NO3 Oxamic acid 3 A' 2600 3432 832 0.758
C3O2 Carbon suboxide 7 Πu 61 95 34 0.643
HCNO fulminic acid 5 Π 224 152 -72 1.475
C5H8 1,4-Pentadiene 16 A 137 291 154 0.471
C5H8 1,4-Pentadiene 17 A 102 85 -17 1.200
C6H10 1,5-Hexadiene 14 Ag 351 268 -83 1.308
C6H10 1,5-Hexadiene 29 Bg 264 215 -49 1.228
COBr2 Carbonic dibromide 4 B1 757 509 -248 1.488
COBr2 Carbonic dibromide 6 B2 512 342 -170 1.499
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 182 -45 1.246
CH3SSCH3 Disulfide, dimethyl 13 A 117 86 -31 1.356
C6H8 1,3,5-Hexatriene, (E)- 36 Bu 170 138 -32 1.229
CH2D2 methane-d2 6 B1 3013 2270 -743 1.327
CH2D2 methane-d2 8 B2 2234 3066 832 0.729
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 343 -113 1.331
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 342 -114 1.333
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 343 -113 1.331
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 342 -114 1.333
LiOH lithium hydroxide 3 Π 257 373 117 0.687
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 218 74 0.661
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 218 74 0.661
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 218 74 0.661
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 218 74 0.661
C2H Ethynyl radical 3 Π 372 279 -93 1.333
CH3OO methylperoxy radical 12 A" 170 137 -33 1.241
CH2OH Hydroxymethyl radical 9 A 234 381 147 0.614
C6H8 1,3,5-Hexatriene, (Z)- 11 A1 1136 876 -260 1.297
C6H8 1,3,5-Hexatriene, (Z)- 19 A2 264 162 -102 1.631
C6H8 1,3,5-Hexatriene, (Z)- 24 B1 358 106 -252 3.373
C4H6 Methylenecyclopropane 17 B1 360 279 -81 1.291
C2Cl2+ dichloroacetylene cation 5 Πu 233 181 -52 1.289
C2Cl2 dichloroacetylene 4 Πg 333 252 -81 1.320
HClO4 perchloric acid 12 A" 191 154 -37 1.240
SF4 Sulfur tetrafluoride 4 A1 228 187 -41 1.218
BF3+ boron trifluoride cation 4 E' 411 269 -142 1.530
BF3+ boron trifluoride cation 3 E' 1662 1204 -458 1.380
ClFO3 Perchloryl fluoride 6 E 405 337 -68 1.201
Cl2O Dichlorine monoxide 3 B2 686 569 -117 1.205
F2SO Thionyl Fluoride 4 A' 378 315 -63 1.200
BrF5 bromine pentafluoride 6 B2 281 193 -88 1.455
BrF5 bromine pentafluoride 8 E 415 344 -71 1.205
ClF3 Chlorine trifluoride 3 A1 328 256 -72 1.280
ClF3 Chlorine trifluoride 6 B2 442 354 -88 1.248
BrF3 Bromine trifluoride 3 A1 242 198 -44 1.221
N2O4 Dinitrogen tetroxide 9 B2u 265 217 -48 1.221
PCl5 Phosphorus pentachloride 2 A1' 370 264 -106 1.402
PCl5 Phosphorus pentachloride 7 E' 100 83 -17 1.211
ZnCN Zinc monocyanide 3 Π 212 176 -36 1.207
ZnCl Zinc monochloride 1 Σ 391 289 -101 1.350
S8 Octasulfur 3 B1 411 316 -95 1.300
S8 Octasulfur 10 E3 437 364 -73 1.200
N2O3 Dinitrogen trioxide 9 A" 63 155 92 0.407
C3 carbon trimer 3 Πu 63 -82 -145 -0.775
B2Cl4 Diboron tetrachloride 9 E 104 87 -17 1.200
SiH- silicon monohydride anion 1 Σ 2175 1761 -414 1.235
SiH- silicon monohydride anion 1 Σ 2175 1761 -414 1.235
SiH- silicon monohydride anion 1 Σ 2175 1761 -414 1.235
SiH- silicon monohydride anion 1 Σ 2175 1761 -414 1.235
ClOO chloroperoxy radical 3 A' 201 312 111 0.646
SF5Cl sulfur chloropentafluoride 5 B1 625 443 -182 1.410
SF5Cl sulfur chloropentafluoride 7 B2 505 299 -206 1.691
H3O+ hydronium 2 A1 954 677 -278 1.410
SF5Cl sulfur chloropentafluoride 11 E 397 236 -161 1.680
Mg2 Magnesium diatomic 1 Σg 51 119 68 0.431
Mg2 Magnesium diatomic 1 Σg 51 119 68 0.430
Mg2 Magnesium diatomic 1 Σg 51 119 68 0.431
Mg2 Magnesium diatomic 1 Σg 51 119 68 0.430
B2H6 Diborane 14 B2u 368 268 -100 1.374
GeH2 germylene 1 A1 1856 892 -964 2.080
GeH2 germylene 2 A1 916 1843 927 0.497
H2OH2O water dimer 6 A' 311 460 149 0.677
H2OH2O water dimer 7 A' 143 270 127 0.529
H2OH2O water dimer 10 A" 523 776 253 0.674
H2OH2O water dimer 11 A" 108 181 73 0.598
H2OH2O water dimer 12 A" 88 -129 -217 -0.682
ZnCH3 Zinc monomethyl 6 E 315 589 274 0.534
H2POH Phosphinous acid 9 A" 375 247 -128 1.520