return to home page Computational Chemistry Comparison and Benchmark DataBase Release 19 (April 2018) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Calculated > Vibrations > Bad Calculations > Bad vib. Calc. vs exp. OR Resources > Bad Calculations > Vibrations > Bad vib. Calc. vs exp.

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
CH3OH Methyl alcohol 12 A" 200 332 132 0.602
C3H6O 2-Propen-1-ol 22 A 377 309 -68 1.221
C3H6O 2-Propen-1-ol 24 A 188 120 -68 1.562
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
C5H12 Propane, 2,2-dimethyl- 12 T1 203 325 122 0.625
C2H3NO3 Oxamic acid 3 A' 2600 3432 832 0.758
C2H3NO3 Oxamic acid 15 A' 328 259 -69 1.268
C2H3NO3 Oxamic acid 21 A" 162 87 -75 1.865
C3H6O Oxetane 12 A2 986 809 -177 1.219
C3H6O Oxetane 18 B1 90 -6 -95 -16.322
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
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 182 -45 1.246
CH3SSCH3 Disulfide, dimethyl 13 A 117 86 -31 1.356
C6H6 Benzvalene 10 A1 996 743 -253 1.341
C6H8 (E)-hexa-1,3,5-triene 36 Bu 170 138 -32 1.229
H2CS- thioformaldehyde anion 4 B1 450 228 -222 1.970
LiOH lithium hydroxide 3 Π 257 373 117 0.687
SiF2+ Silicon difluoride cation 2 A1 350 262 -88 1.333
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 218 74 0.661
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 342 -114 1.333
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 (Z)-hexa-1,3,5-triene 11 A1 1136 876 -260 1.297
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 162 -102 1.631
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 106 -252 3.373
CHCl2 dichloromethyl radical 4 A' 190 272 82 0.698
C4H6 Methylenecyclopropane 17 B1 360 279 -81 1.291
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
BrF3 Bromine trifluoride 3 A1 242 198 -44 1.221
ClF3 Chlorine trifluoride 3 A1 328 257 -71 1.277
ClF3 Chlorine trifluoride 6 B2 442 355 -87 1.246
ZnCl Zinc monochloride 1 Σ 391 289 -101 1.350
OClO- Chlorine dioxide anion 2 A1 418 319 -99 1.311
S8 Octasulfur 3 B1 411 316 -95 1.300
N2O4 Dinitrogen tetroxide 9 B2u 265 217 -48 1.221
N2O3 Dinitrogen trioxide 9 A" 63 155 92 0.407
SF5 Sulfur pentafluoride 3 A1 554 453 -101 1.222
SF5 Sulfur pentafluoride 9 E 387 304 -84 1.275
C3 carbon trimer 3 Πu 63 -82 -145 -0.775
ClOOCl Dichlorine dioxide 1 A 750 1217 467 0.616
SiH- silicon monohydride anion 1 Σ 2175 1761 -414 1.235
H3O+ hydronium cation 2 A1 954 677 -278 1.410
C2H4O4 Formic acid dimer 2 Ag 2949 2038 -911 1.447
C2H4O4 Formic acid dimer 18 Bu 2939 2269 -669 1.295
C2H4O4 Formic acid dimer 24 Bu 268 444 176 0.603
ClOO chloroperoxy radical 3 A' 201 312 111 0.646
B2H6 Diborane 14 B2u 369 268 -101 1.376
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
H2POH Phosphinous acid 9 A" 375 247 -128 1.520
Mg2 Magnesium diatomic 1 Σg 51 119 68 0.430
ClOF3 Chlorine trifluoride oxide 5 A' 319 258 -61 1.238
ClOF3 Chlorine trifluoride oxide 6 A' 224 180 -44 1.242
ClOF3 Chlorine trifluoride oxide 9 A" 412 335 -77 1.228
ZnCH3 Zinc monomethyl 6 E 315 589 274 0.534
ClONO chlorine nitrite 4 A' 406 330 -76 1.228
ClONO chlorine nitrite 5 A' 270 162 -108 1.665
HSO3 HOSO2 3 A 1296 1049 -247 1.236