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/aug-cc-pVTZ
Calculated values were scaled by 0.9566.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 162 49 0.696
C4H10O Ethoxy ethane 20 A2 137 60 -77 2.278
CH3CONH2 Acetamide 20 A 259 190 -69 1.362
CH3COOH Acetic acid 18 torsion A" 93 -125 -218 -0.746
C2H6O2S Dimethyl sulfone 20 B1 262 206 -56 1.270
C2H4+ Ethylene cation 4 torsion Au 84 -442 -526 -0.190
CH3CHO+ acetaldehyde cation 15 A" 145 69 -76 2.089
CH3SCH3+ dimethyl sulfide cation 15 B1 172 118 -54 1.459
CH3CH(CH3)CH3 Isobutane 12 A2 198 139 -59 1.422
CH3CH(CH3)CH3 Isobutane 24 E 280 208 -72 1.348
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 28 -47 2.645
CH3COCH2CH3 2-Butanone 31 torsion A" 201 147 -54 1.364
CH3COCH2CH3 2-Butanone 32 torsion A" 106 -62 -168 -1.723
CH3COCH2CH3 2-Butanone 33 torsion A" 87 -139 -226 -0.628
CH3COOCH3 methyl acetate 26 torsion A" 136 97 -39 1.405
CH3COOCH3 methyl acetate 27 torsion A" 110 -136 -246 -0.810
C6H4Cl2 1,4-dichlorobenzene 30 B3u 122 96 -26 1.266
C6H4O2 parabenzoquinone 30 B3u 109 86 -22 1.258
CH3CH2CH2Br n-propyl bromide 27 torsion A" 133 94 -39 1.418
C3H6O 2-Propen-1-ol 24 A 188 114 -74 1.644
CH2ClCHO chloroacetaldehyde 15 torsion A 27 46 19 0.583
CH2ClCHO chloroacetaldehyde 15 A" 59 148 89 0.397
C5H12 Pentane 23 A2 131 76 -55 1.729
C5H12 Pentane 33 B1 88 127 39 0.694
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 torsion A2 193 126 -67 1.537
C3F6 hexafluoropropene 21 A" 60 36 -24 1.662
CH3CH2CHO Propanal 24 torsion A" 135 106 -29 1.276
C4H9N Pyrrolidine 36 A" 65 103 38 0.633
C4H8O2 1,4-Dioxane 19 Au 288 229 -59 1.256
C5H8 Cyclopentene 18 torsion A' 254 154 -100 1.651
C4H8 cyclobutane 6 torsion A1 199 154 -45 1.289
CH3CHFCH3 2-Fluoropropane 27 A" 243 182 -61 1.339
C4H6O2 2,3-Butanedione 16 torsion Au 48 -67 -115 -0.713
C4H6O2 2,3-Butanedione 21 torsion Bg 240 -48 -288 -5.007
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 1000 -391 1.391
C5H12 Propane, 2,2-dimethyl- 4 A2 198 293 95 0.675
C5H12 Propane, 2,2-dimethyl- 12 T1 203 350 147 0.579
C2H3NO3 Oxamic acid 3 A' 2600 3468 868 0.750
C2H3NO3 Oxamic acid 17 A" 815 643 -172 1.268
C2H3NO3 Oxamic acid 21 A" 162 59 -103 2.723
C3H6O Oxetane 18 B1 90 -91 -181 -0.990
C3O2 Carbon suboxide 7 Πu 61 -22 -83 -2.749
CH3OC2H5 Ethane, methoxy- 29 A" 248 175 -73 1.417
CH3COF Acetyl fluoride 15 torsion A" 123 -82 -205 -1.496
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 666 -2413 4.623
C5H8 1,4-Pentadiene 16 A 137 272 135 0.504
C5H8 1,4-Pentadiene 17 torsion A 102 65 -37 1.575
C5H8 1,4-Pentadiene 17 torsion A 102 65 -37 1.575
C5H8 1,4-Pentadiene 33 torsion B 331 92 -239 3.592
C6H6 Benzvalene 10 A1 996 750 -246 1.328
C6H10 2-Hexyne 41 A" 88 6 -82 15.355
C5H8O Methyl cyclopropyl ketone 35 A" 125 44 -81 2.814
C5H8O Methyl cyclopropyl ketone 36 A" 61 -49 -110 -1.254
H2CS- thioformaldehyde anion 4 B1 450 286 -164 1.574
SiF2+ Silicon difluoride cation 2 A1 350 277 -73 1.264
CFCl2 dichlorofluoromethyl radical 2 A' 747 579 -168 1.290
C2H+ Ethynyl cation 3 Π 550 920 371 0.597
CH3OO methylperoxy radical 12 torsion A" 170 95 -75 1.785
C4H9N Cyclobutylamine 21 A' 174 131 -43 1.326
CH2OH Hydroxymethyl radical 9 torsion A 234 397 163 0.589
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 863 -273 1.316
C6H8 (Z)-hexa-1,3,5-triene 19 torsion A2 264 125 -139 2.115
C6H8 (Z)-hexa-1,3,5-triene 24 torsion B1 358 68 -290 5.240
HCCN cyanomethylene 5 Π 129 -299 -428 -0.431
CHCl2 dichloromethyl radical 4 A' 190 291 101 0.654
C4H6 Methylenecyclopropane 17 B1 360 280 -80 1.284
CH2Cl chloromethyl radical 4 B1 402 184 -218 2.191
BF3+ boron trifluoride cation 5 B2 1791 681 -1110 2.631
BCl3+ Boron Trichloride cation 3 E' 1104 750 -354 1.472
N2O3 Dinitrogen trioxide 9 torsion A" 63 133 70 0.475
AsSe Arsenic monoselenide 1 Σ 280 414 134 0.677
SiC2 Silicon dicarbide 3 B2 196 142 -55 1.386
S3 Sulfur trimer 2 A1 281 599 318 0.469
Br3- tribromide anion 2 Σu 214 141 -73 1.522
GeF Germanium monofluoride 1 Σ 809 636 -173 1.272
ClOO chloroperoxy radical 2 A' 414 228 -186 1.818
ClOO chloroperoxy radical 3 A' 201 89 -112 2.261
Cl3- trichloride anion 2 Σu 327 210 -117 1.556
B5H9 pentaborane9 13 B1 240 585 345 0.410
B5H9 pentaborane9 16 B2 1036 787 -249 1.316
B5H9 pentaborane9 22 E 1409 1038 -371 1.358
OPCl Phosphorus oxychloride 2 A' 308 489 181 0.630
OPCl Phosphorus oxychloride 3 A' 492 299 -193 1.644
H2OH2O water dimer 8 A' 103 161 58 0.639
H2OH2O water dimer 11 A" 108 159 51 0.678
F3- trifluoride anion 2 Σu 550 382 -168 1.440
H2POH Phosphinous acid 9 A" 375 269 -106 1.395
CHFCl Chlorofluoromethyl radical 6 A 540 394 -146 1.371
ZnCH3 Zinc monomethyl 6 E 315 570 255 0.552
NH2NN+ hydrazoic acid, protonated 6 A' 489 351 -138 1.394
H2CNCN cyanamide, methylene 3 A' 2208 2955 747 0.747
H2CNCN cyanamide, methylene 4 A' 1621 2249 628 0.721
C2H3NO Nitrosoethylene 11 A' 490 340 -150 1.439
SNO Nitrogen oxide sulfide 3 A' 792 493 -299 1.608