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 B3LYP/6-31G*
Calculated values were scaled by 0.9603.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 177 64 0.639
CH3CONH2 Acetamide 20 A 259 129 -130 2.006
CH3OH Methyl alcohol 12 A" 200 331 131 0.604
CH3COCH3 Acetone 12 A2 77 33 -44 2.306
C2H6O2S Dimethyl sulfone 20 B1 262 206 -56 1.273
C2H4+ Ethylene cation 4 Au 84 -419 -503 -0.201
CHONH2 formamide 12 A" 289 82 -206 3.511
CH3COCl Acetyl Chloride 15 A" 166 131 -35 1.265
C2F6 hexafluoroethane 4 A1u 68 45 -23 1.511
C3F8 perfluoropropane 13 A2 276 210 -66 1.313
CH3COOCH3 methyl acetate 27 A" 110 50 -60 2.200
C3H6O 2-Propen-1-ol 24 A 188 113 -75 1.669
C4H8S Thiophene, tetrahydro- 5 A 1464 2953 1489 0.496
C4H8S Thiophene, tetrahydro- 6 A 1441 2952 1511 0.488
C4H8S Thiophene, tetrahydro- 7 A 1321 2932 1611 0.451
C4H8S Thiophene, tetrahydro- 8 A 1276 2931 1655 0.435
C4H8S Thiophene, tetrahydro- 11 A 1023 1452 429 0.704
C4H8S Thiophene, tetrahydro- 12 A 888 1451 563 0.612
C4H8S Thiophene, tetrahydro- 13 A 829 1326 497 0.625
C4H8S Thiophene, tetrahydro- 14 A 822 1304 482 0.630
C4H8S Thiophene, tetrahydro- 15 A 678 1274 596 0.532
C4H8S Thiophene, tetrahydro- 16 A 472 1251 779 0.377
C4H8S Thiophene, tetrahydro- 17 A 290 1205 915 0.241
C5H8 Cyclopentene 18 A' 254 134 -120 1.895
C6F6 hexafluorobenzene 7 B2g 719 501 -218 1.435
NH2CN cyanamide 5 A' 408 585 177 0.697
C4H6O2 2,3-Butanedione 21 Bg 240 109 -131 2.199
C5H12 Propane, 2,2-dimethyl- 12 T1 203 299 96 0.679
C2H3NO3 Oxamic acid 3 A' 2600 3453 853 0.753
C2H3NO3 Oxamic acid 15 A' 328 259 -69 1.265
C2H3NO3 Oxamic acid 16 A" 984 785 -199 1.253
C2H3NO3 Oxamic acid 21 A" 162 65 -97 2.498
C3H6O Oxetane 18 B1 90 62 -27 1.438
C3O2 Carbon suboxide 7 Πu 61 124 63 0.491
C5H8 1,4-Pentadiene 16 A 137 288 151 0.475
C6H6 Benzvalene 10 A1 996 742 -254 1.343
C2F2 difluoroacetylene 4 Πg 270 194 -76 1.390
H2CS- thioformaldehyde anion 4 B1 450 -166 -616 -2.706
SiF2+ Silicon difluoride cation 2 A1 350 279 -71 1.255
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 210 66 0.684
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 346 -110 1.319
CH3OO methylperoxy radical 12 A" 170 134 -36 1.269
CH3 Methyl radical 2 A2" 606 435 -172 1.394
CH2OH Hydroxymethyl radical 9 A 234 433 199 0.541
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 865 -271 1.313
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 150 -114 1.757
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 100 -258 3.568
HCCN cyanomethylene 5 Π 129 -279 -408 -0.462
CHCl2 dichloromethyl radical 4 A' 190 293 103 0.649
C4H6 Methylenecyclopropane 17 B1 360 282 -78 1.278
HClO4 perchloric acid 12 A" 191 151 -40 1.268
MgF2 Magnesium fluoride 3 Πu 165 132 -33 1.254
SF4 Sulfur tetrafluoride 4 A1 228 181 -47 1.257
OClO- Chlorine dioxide anion 2 A1 418 324 -94 1.289
SF5 Sulfur pentafluoride 9 E 387 305 -82 1.268
C3O Tricarbon monoxide 5 Π 109 189 80 0.578
C3 carbon trimer 3 Πu 63 178 114 0.357
Cu2 Copper dimer 1 Σg 265 387 122 0.684
Fe(CO)5 Iron pentacarbonyl 5 A2' 383 300 -83 1.275
Fe(CO)5 Iron pentacarbonyl 13 E' 474 377 -98 1.259
Fe(CO)5 Iron pentacarbonyl 15 E' 74 33 -41 2.246
SiH- silicon monohydride anion 1 Σ 2175 1731 -444 1.256
ZnH2 Zinc hydride 3 Πu 633 499 -133 1.267
ClOO chloroperoxy radical 2 A' 414 300 -114 1.378
ClOO chloroperoxy radical 3 A' 201 122 -80 1.657
OPCl Phosphorus oxychloride 2 A' 308 464 156 0.663
OPCl Phosphorus oxychloride 3 A' 492 283 -209 1.739
H2OH2O water dimer 6 A' 311 445 134 0.698
H2OH2O water dimer 7 A' 143 224 81 0.639
H2OH2O water dimer 11 A" 108 164 56 0.659
H2OH2O water dimer 12 A" 88 -65 -153 -1.348
H2POH Phosphinous acid 9 A" 375 241 -134 1.556
ZnCH3 Zinc monomethyl 6 E 315 593 278 0.531
ZnCN Zinc monocyanide 3 Π 212 49 -163 4.288