return to home page Computational Chemistry Comparison and Benchmark DataBase Release 19 (April 2018) Standard Reference Database 101 National Institute of Standards and Technology
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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/6-31G*
Calculated values were scaled by 0.9813.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 349 149 0.573
C2H4+ Ethylene cation 4 Au 84 -793 -877 -0.106
C3F8 perfluoropropane 13 A2 276 199 -77 1.384
C3H6O 2-Propen-1-ol 22 A 377 306 -71 1.234
C3H6O 2-Propen-1-ol 24 A 188 119 -69 1.577
C5H12 Propane, 2,2-dimethyl- 12 T1 203 323 120 0.628
C3O2 Carbon suboxide 7 Πu 61 139 78 0.437
C4H6O2 2,3-Butanedione 21 Bg 240 69 -171 3.460
C4H6O2 2,3-Butanedione 16 Au 48 26 -22 1.818
C4H6O2 2,3-Butanedione 13 Au 1111 887 -224 1.253
HCNO fulminic acid 5 Π 224 -69 -293 -3.248
C3H6O Oxetane 18 B1 90 -62 -152 -1.453
C3H6O Oxetane 12 A2 986 805 -181 1.225
C2H3NO3 Oxamic acid 21 A" 162 86 -76 1.875
C2H3NO3 Oxamic acid 16 A" 984 790 -194 1.246
C2H3NO3 Oxamic acid 15 A' 328 257 -71 1.276
C2H3NO3 Oxamic acid 3 A' 2600 3420 820 0.760
C5H8 1,4-Pentadiene 16 A 137 285 148 0.481
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 181 -46 1.255
CH3SSCH3 Disulfide, dimethyl 13 A 117 71 -46 1.644
C6H6 Benzvalene 10 A1 996 744 -252 1.339
C2F2 difluoroacetylene 4 Πg 270 166 -104 1.627
C6H8 (E)-hexa-1,3,5-triene 36 Bu 170 136 -34 1.252
H2CS- thioformaldehyde anion 4 B1 450 117 -333 3.854
CuO Copper Monoxide 1 Σ 640 931 291 0.687
SiF2+ Silicon difluoride cation 2 A1 350 272 -78 1.286
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 218 74 0.660
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 340 -116 1.339
C2H Ethynyl radical 3 Π 372 -342 -713 -1.088
CH3 Methyl radical 2 A2" 606 476 -131 1.275
CH3OO methylperoxy radical 12 A" 170 134 -36 1.269
CH2OH Hydroxymethyl radical 9 A 234 439 205 0.533
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 879 -257 1.293
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 166 -98 1.590
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 109 -249 3.291
HCCN cyanomethylene 5 Π 129 -207 -336 -0.623
CHCl2 dichloromethyl radical 4 A' 190 284 94 0.668
C4H6 Methylenecyclopropane 17 B1 360 279 -81 1.289
C2Cl2 dichloroacetylene 4 Πg 333 245 -88 1.358
HClO4 perchloric acid 12 A" 191 151 -40 1.268
MgF2 Magnesium fluoride 3 Πu 165 134 -31 1.232
SF4 Sulfur tetrafluoride 4 A1 228 177 -51 1.290
CaF2 Calcium difluoride 2 A1 120 19 -101 6.250
OClO- Chlorine dioxide anion 2 A1 418 335 -83 1.249
SF5 Sulfur pentafluoride 9 E 387 307 -80 1.260
C3O Tricarbon monoxide 5 Π 109 192 83 0.567
C3 carbon trimer 3 Πu 63 137 74 0.461
ClOOCl Dichlorine dioxide 1 A 750 1155 405 0.650
N2O3 Dinitrogen trioxide 9 A" 63 151 88 0.417
SiH- silicon monohydride anion 1 Σ 2175 1743 -432 1.248
ZnH2 Zinc hydride 3 Πu 633 490 -142 1.291
C2H4O4 Formic acid dimer 2 Ag 2949 2171 -778 1.358
C2H4O4 Formic acid dimer 18 Bu 2939 2410 -528 1.219
C2H4O4 Formic acid dimer 24 Bu 268 393 125 0.681
ClOO chloroperoxy radical 3 A' 201 316 115 0.637
B2H6 Diborane 14 B2u 369 257 -112 1.436
H2POH Phosphinous acid 9 A" 375 244 -131 1.539
Mg2 Magnesium diatomic 1 Σg 51 119 68 0.430
ClOF3 Chlorine trifluoride oxide 6 A' 224 181 -43 1.239
ZnCH3 Zinc monomethyl 6 E 315 593 278 0.532
ClONO chlorine nitrite 5 A' 270 185 -85 1.462
HSO3 HOSO2 3 A 1296 1050 -246 1.234
H2OH2O water dimer 12 A" 88 -196 -284 -0.448
H2OH2O water dimer 11 A" 108 207 99 0.522
H2OH2O water dimer 10 A" 523 806 283 0.649
H2OH2O water dimer 7 A' 143 341 198 0.419
H2OH2O water dimer 6 A' 311 612 301 0.508
ZnCN Zinc monocyanide 3 Π 212 -116 -328 -1.829