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-pVDZ
Calculated values were scaled by 0.9526.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 162 49 0.699
C4H10O Ethoxy ethane 20 A2 137 71 -66 1.936
CH3COOH Acetic acid 18 torsion A" 93 -107 -200 -0.871
CH3OH Methyl alcohol 12 torsion A" 200 319 119 0.627
C2H6O2S Dimethyl sulfone 20 B1 262 203 -59 1.288
C2H4+ Ethylene cation 4 torsion Au 84 -410 -494 -0.205
CH3CHO+ acetaldehyde cation 15 A" 145 100 -45 1.453
CH3SCH3+ dimethyl sulfide cation 15 B1 172 118 -54 1.463
CH3COCl Acetyl Chloride 15 torsion A" 166 128 -38 1.294
C3F8 perfluoropropane 13 A2 276 217 -59 1.271
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 29 -46 2.595
CH3COCH2CH3 2-Butanone 32 torsion A" 106 -41 -147 -2.606
CH3COCH2CH3 2-Butanone 33 torsion A" 87 -126 -213 -0.689
CH3COOCH3 methyl acetate 27 torsion A" 110 -120 -230 -0.914
C6H4Cl2 1,4-dichlorobenzene 30 B3u 122 96 -26 1.266
C3H6O 2-Propen-1-ol 24 A 188 110 -78 1.713
CH2ClCHO chloroacetaldehyde 15 torsion A 27 54 27 0.502
CH2ClCHO chloroacetaldehyde 15 A" 59 139 80 0.424
C5H12 Pentane 23 A2 131 82 -49 1.589
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 torsion A2 193 130 -63 1.480
C3F6 hexafluoropropene 21 A" 60 27 -33 2.239
C4H9N Pyrrolidine 36 A" 65 94 29 0.689
C5H8 Cyclopentene 18 torsion A' 254 155 -99 1.640
CF3CHF2 pentafluoroethane 18 torsion A" 75 54 -21 1.392
CH3CHFCH3 2-Fluoropropane 27 A" 243 192 -51 1.269
C4H6O2 2,3-Butanedione 16 torsion Au 48 -71 -119 -0.674
C4H6O2 2,3-Butanedione 21 torsion Bg 240 -58 -298 -4.115
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 1011 -380 1.376
C6H4 Benzyne 24 B2 472 374 -98 1.261
C5H12 Propane, 2,2-dimethyl- 12 T1 203 340 137 0.598
C2H3NO3 Oxamic acid 3 A' 2600 3466 866 0.750
C2H3NO3 Oxamic acid 15 A' 328 248 -80 1.325
C2H3NO3 Oxamic acid 17 A" 815 641 -174 1.271
C2H3NO3 Oxamic acid 21 A" 162 60 -102 2.683
C3H6O Oxetane 18 B1 90 -76 -165 -1.187
CH3OC2H5 Ethane, methoxy- 29 A" 248 187 -61 1.329
CH3COF Acetyl fluoride 15 torsion A" 123 -51 -174 -2.432
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 664 -2415 4.638
C5H8 1,4-Pentadiene 16 A 137 275 138 0.498
C5H8 1,4-Pentadiene 17 torsion A 102 71 -31 1.432
C5H8 1,4-Pentadiene 17 torsion A 102 71 -31 1.432
C5H8 1,4-Pentadiene 33 torsion B 331 91 -240 3.646
C6H6 Benzvalene 10 A1 996 730 -266 1.364
C6H10 2-Hexyne 41 A" 88 43 -45 2.065
C5H8O Methyl cyclopropyl ketone 35 A" 125 53 -72 2.367
C5H8O Methyl cyclopropyl ketone 36 A" 61 15 -46 4.147
H2CS- thioformaldehyde anion 4 B1 450 -88 -538 -5.086
SiF2+ Silicon difluoride cation 2 A1 350 254 -96 1.380
CFCl2 dichlorofluoromethyl radical 2 A' 747 590 -157 1.267
C2H+ Ethynyl cation 3 Π 550 940 390 0.585
CH3OO methylperoxy radical 12 torsion A" 170 111 -59 1.535
CH3 Methyl radical 2 torsion A2" 606 435 -172 1.395
CH2OH Hydroxymethyl radical 9 torsion A 234 407 173 0.575
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 860 -276 1.322
C6H8 (Z)-hexa-1,3,5-triene 19 torsion A2 264 96 -168 2.742
C6H8 (Z)-hexa-1,3,5-triene 24 torsion B1 358 72 -286 5.004
HCCN cyanomethylene 5 Π 129 -301 -429 -0.429
CHCl2 dichloromethyl radical 4 A' 190 291 101 0.653
CH3CSCH3 Thioacetone 17 B1 153 120 -33 1.273
C4H6 Methylenecyclopropane 17 B1 360 279 -81 1.290
CH2Cl chloromethyl radical 4 B1 402 -131 -533 -3.079
C2Cl2+ dichloroacetylene cation 5 Πu 233 184 -49 1.264
BF3+ boron trifluoride cation 5 B2 1791 657 -1134 2.726
CaBr2 Calcium dibromide 3 Πu 72 32 -40 2.270
BCl3+ Boron Trichloride cation 3 E' 1104 779 -325 1.418
N2O3 Dinitrogen trioxide 9 torsion A" 63 127 64 0.495
AsSe Arsenic monoselenide 1 Σ 280 414 134 0.676
SiC2 Silicon dicarbide 3 B2 196 61 -136 3.227
C3 carbon trimer 3 Πu 63 161 97 0.395
S3 Sulfur trimer 2 A1 281 593 312 0.474
SiH2D2 silane-d2 6 B1 2183 1496 -687 1.459
SiH2D2 silane-d2 8 B2 1601 2070 469 0.773
Br3- tribromide anion 2 Σu 214 155 -59 1.377
FOO Dioxygen monofluoride radical 3 A' 376 259 -117 1.452
ClOO chloroperoxy radical 2 A' 414 218 -196 1.896
ClOO chloroperoxy radical 3 A' 201 107 -95 1.890
Cl3- trichloride anion 2 Σu 327 207 -120 1.581
BH3PH3 borane phosphine 12 E 447 352 -95 1.271
B5H9 pentaborane9 13 B1 240 582 342 0.413
B5H9 pentaborane9 16 B2 1036 770 -266 1.345
B5H9 pentaborane9 18 B2 600 470 -130 1.277
B5H9 pentaborane9 22 E 1409 1016 -393 1.387
OPCl Phosphorus oxychloride 2 A' 308 486 178 0.634
OPCl Phosphorus oxychloride 3 A' 492 293 -199 1.682
H2OH2O water dimer 7 A' 143 205 62 0.696
H2OH2O water dimer 11 A" 108 173 65 0.622
H2OH2O water dimer 12 A" 88 60 -28 1.458
F3- trifluoride anion 2 Σu 550 432 -118 1.272
H2POH Phosphinous acid 9 A" 375 266 -109 1.409
CHFCl Chlorofluoromethyl radical 6 A 540 390 -150 1.385
ZnCH3 Zinc monomethyl 6 E 315 580 265 0.543
NH2NN+ hydrazoic acid, protonated 6 A' 489 376 -113 1.299
H2CNCN cyanamide, methylene 3 A' 2208 2946 738 0.750
H2CNCN cyanamide, methylene 4 A' 1621 2249 628 0.721
C2H3NO Nitrosoethylene 11 A' 490 330 -160 1.487
SNO Nitrogen oxide sulfide 3 A' 792 491 -302 1.615