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 HSEh1PBE/6-31G*
Calculated values were scaled by 0.951.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 330 130 0.605
C3H4O2 β–Propiolactone 21 A" 113 174 61 0.649
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 306 92 0.699
CH3COCH3 Acetone 12 A2 77 23 -54 3.330
CH3COOH Acetic acid 18 A" 93 73 -20 1.278
CHONH2 formamide 12 A" 289 139 -150 2.076
CH3COCH2CH3 2-Butanone 33 A" 87 -25 -112 -3.438
C2F6 hexafluoroethane 4 A1u 68 47 -21 1.450
CH3COOCH3 methyl acetate 27 A" 110 47 -63 2.354
C3H6O 2-Propen-1-ol 24 A 188 113 -75 1.670
C5H8 Cyclopentene 18 A' 254 143 -111 1.782
C4H6O2 2,3-Butanedione 21 Bg 240 103 -137 2.338
C6F6 hexafluorobenzene 7 B2g 719 507 -212 1.418
C2H3NO3 Oxamic acid 15 A' 328 257 -71 1.278
C2H3NO3 Oxamic acid 21 A" 162 68 -94 2.390
C5H12 Propane, 2,2-dimethyl- 12 T1 203 304 101 0.667
C2H3NO3 Oxamic acid 3 A' 2600 3453 853 0.753
C3H6O Oxetane 18 B1 90 36 -54 2.521
C3O2 Carbon suboxide 7 Πu 61 114 53 0.537
C5H8 1,4-Pentadiene 16 A 137 285 148 0.481
C6H6 Benzvalene 10 A1 996 744 -252 1.338
H2CS- thioformaldehyde anion 4 B1 450 -91 -541 -4.948
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 342 -114 1.334
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 208 64 0.692
NaOH sodium hydroxide 3 Π 300 -145 -445 -2.067
C2H+ Ethynyl cation 3 Π 550 893 343 0.616
CH3 Methyl radical 2 A2" 606 441 -166 1.376
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 1.765
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 100 -258 3.581
CH2OH Hydroxymethyl radical 9 A 234 423 189 0.553
HCCN cyanomethylene 5 Π 129 -295 -424 -0.436
CHCl2 dichloromethyl radical 4 A' 190 296 106 0.643
C4H6 Methylenecyclopropane 17 B1 360 280 -80 1.284
C2Cl2+ dichloroacetylene cation 5 Πu 233 179 -54 1.305
Cu2 Copper dimer 1 Σg 265 384 120 0.688
N2O3 Dinitrogen trioxide 9 A" 63 142 79 0.445
C3O Tricarbon monoxide 5 Π 109 173 64 0.630
C3 carbon trimer 3 Πu 63 136 72 0.467
ZnH2 Zinc hydride 3 Πu 633 492 -140 1.285
H2POH Phosphinous acid 9 A" 375 250 -125 1.499
ClOO chloroperoxy radical 2 A' 414 290 -124 1.427
ClOO chloroperoxy radical 3 A' 201 129 -72 1.560
OPCl Phosphorus oxychloride 2 A' 308 483 175 0.637
OPCl Phosphorus oxychloride 3 A' 492 291 -201 1.692
H2OH2O water dimer 7 A' 143 229 86 0.625
H2OH2O water dimer 11 A" 108 165 57 0.653
H2OH2O water dimer 12 A" 88 30 -58 2.955
Mg2 Magnesium diatomic 1 Σg 51 88 37 0.583
Al2 Aluminum diatomic 1 Σg 286 207 -79 1.379
ZnCH3 Zinc monomethyl 6 E 315 592 277 0.532
ZnCN Zinc monocyanide 3 Π 212 59 -153 3.619