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 0.9608.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 177 64 0.638
CH3CONH2 Acetamide 20 A 259 106 -153 2.446
CH3OH Methyl alcohol 12 A" 200 323 123 0.620
CH3COCH3 Acetone 12 A2 77 39 -38 1.974
C2H6O2S Dimethyl sulfone 20 B1 262 206 -56 1.272
C2H4+ Ethylene cation 4 Au 84 -447 -531 -0.188
CHONH2 formamide 12 A" 289 158 -131 1.831
CH3COCl Acetyl Chloride 15 A" 166 130 -36 1.274
C2F6 hexafluoroethane 4 A1u 68 45 -23 1.510
C3F8 perfluoropropane 13 A2 276 210 -66 1.313
CH3COOCH3 methyl acetate 27 A" 110 44 -66 2.497
C3H6O 2-Propen-1-ol 24 A 188 112 -76 1.682
C4H8S Thiophene, tetrahydro- 5 A 1464 2951 1487 0.496
C4H8S Thiophene, tetrahydro- 6 A 1441 2950 1509 0.488
C4H8S Thiophene, tetrahydro- 7 A 1321 2930 1609 0.451
C4H8S Thiophene, tetrahydro- 8 A 1276 2930 1654 0.435
C4H8S Thiophene, tetrahydro- 11 A 1023 1438 415 0.711
C4H8S Thiophene, tetrahydro- 12 A 888 1436 548 0.618
C4H8S Thiophene, tetrahydro- 13 A 829 1317 488 0.629
C4H8S Thiophene, tetrahydro- 14 A 822 1295 473 0.635
C4H8S Thiophene, tetrahydro- 15 A 678 1264 586 0.536
C4H8S Thiophene, tetrahydro- 16 A 472 1242 770 0.380
C4H8S Thiophene, tetrahydro- 17 A 290 1198 908 0.242
C5H8 Cyclopentene 18 A' 254 134 -120 1.894
C6F6 hexafluorobenzene 7 B2g 719 501 -218 1.434
C4H6O2 2,3-Butanedione 21 Bg 240 101 -139 2.380
C5H12 Propane, 2,2-dimethyl- 12 T1 203 299 96 0.678
C2H3NO3 Oxamic acid 3 A' 2600 3462 862 0.751
C2H3NO3 Oxamic acid 15 A' 328 260 -68 1.260
C2H3NO3 Oxamic acid 16 A" 984 784 -200 1.255
C2H3NO3 Oxamic acid 21 A" 162 67 -95 2.410
C3H6O Oxetane 18 B1 90 61 -29 1.480
C3O2 Carbon suboxide 7 Πu 61 124 63 0.491
C5H8 1,4-Pentadiene 16 A 137 287 150 0.477
C6H6 Benzvalene 10 A1 996 743 -253 1.340
C2F2 difluoroacetylene 4 Πg 270 194 -76 1.389
H2CS- thioformaldehyde anion 4 B1 450 -140 -590 -3.208
SiF2+ Silicon difluoride cation 2 A1 350 279 -71 1.254
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 209 65 0.689
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 346 -110 1.318
CH3OO methylperoxy radical 12 A" 170 129 -41 1.321
CH3 Methyl radical 2 A2" 606 444 -163 1.366
CH2OH Hydroxymethyl radical 9 A 234 422 188 0.554
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 864 -272 1.315
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 151 -113 1.754
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 102 -256 3.524
HCCN cyanomethylene 5 Π 129 -266 -395 -0.484
CHCl2 dichloromethyl radical 4 A' 190 293 103 0.649
C4H6 Methylenecyclopropane 17 B1 360 283 -77 1.274
HClO4 perchloric acid 12 A" 191 131 -60 1.455
MgF2 Magnesium fluoride 3 Πu 165 132 -33 1.253
SF4 Sulfur tetrafluoride 4 A1 228 181 -47 1.256
OClO- Chlorine dioxide anion 2 A1 418 325 -93 1.288
N2O3 Dinitrogen trioxide 9 A" 63 141 78 0.446
SF5 Sulfur pentafluoride 9 E 387 306 -82 1.267
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 265 387 123 0.683
SiH- silicon monohydride anion 1 Σ 2175 1741 -434 1.249
H3O+ hydronium cation 2 A1 954 754 -200 1.266
ZnH2 Zinc hydride 3 Πu 633 485 -147 1.304
ClOO chloroperoxy radical 2 A' 414 300 -113 1.378
ClOO chloroperoxy radical 3 A' 201 122 -80 1.656
OPCl Phosphorus oxychloride 2 A' 308 464 156 0.663
OPCl Phosphorus oxychloride 3 A' 492 283 -209 1.738
H2OH2O water dimer 7 A' 143 211 68 0.679
H2OH2O water dimer 11 A" 108 167 59 0.646
H2OH2O water dimer 12 A" 88 35 -53 2.548
H2POH Phosphinous acid 9 A" 375 243 -132 1.545
ZnCH3 Zinc monomethyl 6 E 315 595 280 0.529
ZnCN Zinc monocyanide 3 Π 212 49 -163 4.286