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" 200 339 139 0.590
C3H6O 2-Propen-1-ol 22 A 377 304 -73 1.241
C3H6O 2-Propen-1-ol 24 A 188 119 -69 1.586
C4H6O2 2,3-Butanedione 13 Au 1111 874 -237 1.272
C4H6O2 2,3-Butanedione 16 Au 48 -34 -82 -1.421
C4H6O2 2,3-Butanedione 21 Bg 240 47 -193 5.073
C5H12 Propane, 2,2-dimethyl- 12 T1 203 323 120 0.629
C2H3NO3 Oxamic acid 3 A' 2600 3424 824 0.759
C2H3NO3 Oxamic acid 15 A' 328 257 -71 1.279
C2H3NO3 Oxamic acid 16 A" 984 787 -197 1.250
C2H3NO3 Oxamic acid 21 A" 162 87 -75 1.868
C3H6O Oxetane 12 A2 986 800 -186 1.233
C3H6O Oxetane 18 B1 90 -63 -153 -1.431
C3O2 Carbon suboxide 7 Πu 61 139 78 0.437
HCNO fulminic acid 5 Π 224 42 -182 5.305
C5H8 1,4-Pentadiene 16 A 137 284 147 0.483
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 180 -47 1.259
CH3SSCH3 Disulfide, dimethyl 13 A 117 73 -44 1.596
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 450 142 -308 3.163
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' 144 216 72 0.666
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 340 -116 1.340
CH3OO methylperoxy radical 12 A" 170 126 -44 1.351
CH3 Methyl radical 2 A2" 606 482 -124 1.257
CH2OH Hydroxymethyl radical 9 A 234 427 193 0.548
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 875 -261 1.298
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 166 -98 1.594
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 109 -249 3.288
HCCN cyanomethylene 5 Π 129 -179 -308 -0.721
CHCl2 dichloromethyl radical 4 A' 190 280 90 0.679
C4H6 Methylenecyclopropane 17 B1 360 280 -80 1.285
C2Cl2 dichloroacetylene 4 Πg 333 245 -88 1.358
HClO4 perchloric acid 12 A" 191 127 -64 1.510
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
N2O3 Dinitrogen trioxide 9 A" 63 151 88 0.417
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
SiH- silicon monohydride anion 1 Σ 2175 1752 -423 1.241
H3O+ hydronium cation 2 A1 954 693 -262 1.378
ZnH2 Zinc hydride 3 Πu 633 470 -163 1.347
C2H4O4 Formic acid dimer 2 Ag 2949 1897 -1052 1.555
C2H4O4 Formic acid dimer 18 Bu 2939 2067 -872 1.422
C2H4O4 Formic acid dimer 24 Bu 268 490 222 0.547
ClOO chloroperoxy radical 3 A' 201 316 115 0.637
B2H6 Diborane 14 B2u 369 262 -106 1.406
H2OH2O water dimer 6 A' 311 585 274 0.531
H2OH2O water dimer 7 A' 143 327 184 0.437
H2OH2O water dimer 10 A" 523 785 262 0.666
H2OH2O water dimer 11 A" 108 205 97 0.527
H2OH2O water dimer 12 A" 88 -206 -294 -0.428
H2POH Phosphinous acid 9 A" 375 244 -132 1.540
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 315 594 279 0.531
ClONO chlorine nitrite 5 A' 270 185 -85 1.462
ZnCN Zinc monocyanide 3 Π 212 -116 -328 -1.829
HSO3 HOSO2 3 A 1296 1047 -249 1.237