return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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Bad vibrational frequency predictions

19 02 11 15 45

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 wB97X-D/cc-pVTZ
Calculated values were scaled by 0.956.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 164 51 0.688
C4H10O Ethoxy ethane 20 A2 137 60 -77 2.293
CH3CONH2 Acetamide 20 A 259 152 -107 1.706
CH3COOH Acetic acid 18 torsion A" 93 -120 -213 -0.776
CH3OH Methyl alcohol 12 torsion A" 200 288 88 0.693
C2H6O2S Dimethyl sulfone 20 B1 262 203 -59 1.291
C2H4+ Ethylene cation 4 torsion Au 84 -434 -518 -0.194
CH3CHO+ acetaldehyde cation 15 A" 145 67 -78 2.153
CHONH2 formamide 12 torsion A" 289 219 -70 1.320
CH3SCH3+ dimethyl sulfide cation 15 B1 172 113 -59 1.517
CH3CH(CH3)CH3 Isobutane 12 A2 198 138 -60 1.432
CH3CH(CH3)CH3 Isobutane 24 E 280 206 -74 1.359
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 21 -54 3.644
CH3COCH2CH3 2-Butanone 31 torsion A" 201 148 -53 1.358
CH3COCH2CH3 2-Butanone 32 torsion A" 106 -59 -165 -1.797
CH3COCH2CH3 2-Butanone 33 torsion A" 87 -135 -222 -0.644
CH3COOCH3 methyl acetate 26 torsion A" 136 92 -44 1.486
CH3COOCH3 methyl acetate 27 torsion A" 110 -133 -243 -0.828
C6H4Cl2 1,4-dichlorobenzene 30 B3u 122 97 -25 1.261
CH3CH2CH2Br n-propyl bromide 27 torsion A" 133 96 -37 1.389
C3H6O 2-Propen-1-ol 24 A 188 116 -73 1.629
CH2ClCHO chloroacetaldehyde 15 torsion A 27 55 28 0.493
CH2ClCHO chloroacetaldehyde 15 A" 59 149 90 0.397
C5H12 Pentane 23 A2 131 79 -52 1.655
C5H12 Pentane 33 B1 88 127 39 0.695
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 torsion A2 193 124 -69 1.562
C3F6 hexafluoropropene 21 A" 60 34 -26 1.745
C4H9N Pyrrolidine 36 A" 65 99 34 0.658
C4H8O2 1,4-Dioxane 19 Au 288 226 -62 1.277
C5H8 Cyclopentene 18 torsion A' 254 153 -101 1.662
C4H8 cyclobutane 6 torsion A1 199 154 -45 1.291
CH3CHFCH3 2-Fluoropropane 27 A" 243 180 -63 1.352
C4H6O2 2,3-Butanedione 16 torsion Au 48 -70 -118 -0.683
C4H6O2 2,3-Butanedione 21 torsion Bg 240 -53 -293 -4.506
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 1002 -389 1.388
C5H12 Propane, 2,2-dimethyl- 4 A2 198 290 92 0.683
C5H12 Propane, 2,2-dimethyl- 12 T1 203 347 144 0.586
C2H3NO3 Oxamic acid 3 A' 2600 3469 869 0.749
C2H3NO3 Oxamic acid 17 A" 815 646 -169 1.261
C2H3NO3 Oxamic acid 21 A" 162 59 -103 2.744
C3H6O Oxetane 18 B1 90 -77 -167 -1.160
C3O2 Carbon suboxide 7 Πu 61 -18 -79 -3.304
CH3OC2H5 Ethane, methoxy- 29 A" 248 173 -75 1.433
CH3COF Acetyl fluoride 15 torsion A" 123 -79 -202 -1.561
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 666 -2413 4.624
C5H8 1,4-Pentadiene 16 A 137 271 134 0.506
C5H8 1,4-Pentadiene 17 torsion A 102 63 -39 1.615
C5H8 1,4-Pentadiene 17 torsion A 102 63 -39 1.615
C5H8 1,4-Pentadiene 33 torsion B 331 91 -240 3.636
C6H6 Benzvalene 10 A1 996 751 -245 1.327
C6H10 2-Hexyne 41 A" 88 17 -71 5.099
C5H8O Methyl cyclopropyl ketone 35 A" 125 46 -79 2.713
C5H8O Methyl cyclopropyl ketone 36 A" 61 -30 -91 -2.001
H2CS- thioformaldehyde anion 4 B1 450 207 -243 2.177
NaOH sodium hydroxide 3 torsion Π 300 222 -78 1.353
SiF2+ Silicon difluoride cation 2 A1 350 277 -73 1.264
CFCl2 dichlorofluoromethyl radical 2 A' 747 581 -166 1.287
C2H+ Ethynyl cation 3 Π 550 918 369 0.598
CH3OO methylperoxy radical 12 torsion A" 170 89 -81 1.915
C4H9N Cyclobutylamine 21 A' 174 138 -36 1.262
CH2OH Hydroxymethyl radical 9 torsion A 234 403 169 0.581
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 863 -273 1.317
C6H8 (Z)-hexa-1,3,5-triene 19 torsion A2 264 126 -138 2.101
C6H8 (Z)-hexa-1,3,5-triene 24 torsion B1 358 68 -290 5.276
HCCN cyanomethylene 5 Π 129 -297 -426 -0.434
CHCl2 dichloromethyl radical 4 A' 190 291 101 0.654
C4H6 Methylenecyclopropane 17 B1 360 280 -80 1.285
CH2Cl chloromethyl radical 4 B1 402 177 -225 2.270
BF3+ boron trifluoride cation 5 B2 1791 677 -1114 2.645
CaBr2 Calcium dibromide 3 Πu 72 29 -43 2.484
BCl3+ Boron Trichloride cation 3 E' 1104 753 -351 1.467
N2O3 Dinitrogen trioxide 9 torsion A" 63 135 72 0.465
AsSe Arsenic monoselenide 1 Σ 280 414 134 0.676
SiC2 Silicon dicarbide 3 B2 196 143 -54 1.376
S3 Sulfur trimer 2 A1 281 600 319 0.468
Br3- tribromide anion 2 Σu 214 142 -72 1.503
ClOO chloroperoxy radical 2 A' 414 229 -184 1.803
ClOO chloroperoxy radical 3 A' 201 93 -109 2.171
Cl3- trichloride anion 2 Σu 327 218 -109 1.498
B5H9 pentaborane9 13 B1 240 585 345 0.410
B5H9 pentaborane9 16 B2 1036 787 -249 1.316
B5H9 pentaborane9 22 E 1409 1037 -372 1.358
OPCl Phosphorus oxychloride 2 A' 308 491 183 0.628
OPCl Phosphorus oxychloride 3 A' 492 300 -192 1.640
H2OH2O water dimer 8 A' 103 154 51 0.667
H2POH Phosphinous acid 9 A" 375 273 -102 1.376
CHFCl Chlorofluoromethyl radical 6 A 540 394 -146 1.371
ZnCH3 Zinc monomethyl 6 E 315 572 257 0.551
NH2NN+ hydrazoic acid, protonated 6 A' 489 324 -165 1.509
H2CNCN cyanamide, methylene 3 A' 2208 2954 746 0.747
H2CNCN cyanamide, methylene 4 A' 1621 2252 631 0.720
C2H3NO Nitrosoethylene 11 A' 490 339 -151 1.446
SNO Nitrogen oxide sulfide 3 A' 792 492 -301 1.612