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/6-31+G**
Calculated values were scaled by 0.9523.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 162 49 0.700
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" 200 304 104 0.658
C2H4+ Ethylene cation 4 torsion Au 84 -410 -494 -0.205
CH3CHO+ acetaldehyde cation 15 A" 145 67 -78 2.172
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 2.596
CH3COCH2CH3 2-Butanone 32 torsion A" 106 -41 -147 -2.607
CH3COCH2CH3 2-Butanone 33 torsion A" 87 -126 -213 -0.689
CH3COOCH3 methyl acetate 27 torsion A" 110 -120 -230 -0.914
C2Br4 tetrabromoethene 7 B2g 464 993 529 0.467
C6H4Cl2 1,4-dichlorobenzene 30 B3u 122 96 -26 1.268
CH2BrCH2Br Ethane, 1,2-dibromo- 10 A 91 70 -21 1.309
C3H6O 2-Propen-1-ol 24 A 188 110 -78 1.713
CH2ClCHO chloroacetaldehyde 15 torsion A 27 54 27 0.503
CH2ClCHO chloroacetaldehyde 15 A" 59 139 80 0.424
C5H12 Pentane 23 A2 131 82 -49 1.590
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 torsion A2 193 130 -63 1.480
C3F6 hexafluoropropene 21 A" 60 24 -36 2.481
C4H9N Pyrrolidine 36 A" 65 94 29 0.689
C5H8 Cyclopentene 18 torsion A' 254 155 -99 1.640
CH3CHFCH3 2-Fluoropropane 27 A" 243 190 -53 1.280
C4H6O2 2,3-Butanedione 16 torsion Au 48 -71 -119 -0.674
C4H6O2 2,3-Butanedione 21 torsion Bg 240 -58 -298 -4.116
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 996 -395 1.397
C6H4 Benzyne 24 B2 472 374 -98 1.262
C5H12 Propane, 2,2-dimethyl- 12 T1 203 340 137 0.598
C2H3NO3 Oxamic acid 3 A' 2600 3465 865 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 2.684
C3H6O Oxetane 18 B1 90 -76 -165 -1.187
C3O2 Carbon suboxide 7 Πu 61 154 93 0.395
HCNO fulminic acid 5 torsion Π 224 339 115 0.662
CH3OC2H5 Ethane, methoxy- 29 A" 248 187 -61 1.329
CH3COF Acetyl fluoride 15 torsion A" 123 -51 -174 -2.433
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 679 -2400 4.535
C5H8 1,4-Pentadiene 16 A 137 275 138 0.498
C5H8 1,4-Pentadiene 17 torsion A 102 71 -31 1.433
C5H8 1,4-Pentadiene 17 torsion A 102 71 -31 1.433
C5H8 1,4-Pentadiene 33 torsion B 331 91 -240 3.647
HCCBr bromoacetylene 5 Π 295 445 150 0.663
C6H6 Benzvalene 10 A1 996 744 -252 1.339
C6H10 2-Hexyne 41 A" 88 43 -45 2.066
C5H8O Methyl cyclopropyl ketone 35 A" 125 53 -72 2.368
C5H8O Methyl cyclopropyl ketone 36 A" 61 15 -46 4.148
H2CS- thioformaldehyde anion 4 B1 450 276 -174 1.629
SiF2+ Silicon difluoride cation 2 A1 350 272 -78 1.287
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 1.536
CH2OH Hydroxymethyl radical 9 torsion A 234 407 173 0.576
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 859 -277 1.322
C6H8 (Z)-hexa-1,3,5-triene 19 torsion A2 264 96 -168 2.743
C6H8 (Z)-hexa-1,3,5-triene 24 torsion B1 358 72 -286 5.006
HCCN cyanomethylene 5 Π 129 -300 -429 -0.429
CHCl2 dichloromethyl radical 4 A' 190 295 105 0.643
CH3CSCH3 Thioacetone 17 B1 153 120 -33 1.273
C4H6 Methylenecyclopropane 17 B1 360 279 -81 1.290
CH2Cl chloromethyl radical 4 B1 402 182 -220 2.207
C2Cl2+ dichloroacetylene cation 5 Πu 233 184 -49 1.265
BF3+ boron trifluoride cation 5 B2 1791 657 -1134 2.727
BeBr2 Beryllium bromide 3 Πu 207 297 90 0.697
BCl3+ Boron Trichloride cation 3 E' 1104 766 -338 1.442
N2O3 Dinitrogen trioxide 9 torsion A" 63 127 64 0.495
C3O Tricarbon monoxide 5 Π 109 186 77 0.586
AsSe Arsenic monoselenide 1 Σ 280 420 140 0.666
SiC2 Silicon dicarbide 3 B2 196 52 -144 3.773
C3 carbon trimer 3 Πu 63 160 97 0.395
S3 Sulfur trimer 2 A1 281 585 304 0.480
SiH2D2 silane-d2 6 B1 2183 1529 -654 1.428
SiH2D2 silane-d2 8 B2 1601 2116 515 0.757
H3O+ hydronium cation 2 A1 954 732 -222 1.304
Br3- tribromide anion 2 Σu 214 158 -56 1.353
FOO Dioxygen monofluoride radical 3 A' 376 259 -117 1.452
ClOO chloroperoxy radical 2 A' 414 218 -196 1.897
ClOO chloroperoxy radical 3 A' 201 107 -95 1.891
Cl3- trichloride anion 2 Σu 327 207 -120 1.582
B5H9 pentaborane9 13 B1 240 594 354 0.404
B5H9 pentaborane9 16 B2 1036 781 -255 1.327
B5H9 pentaborane9 22 E 1409 1047 -362 1.346
OPCl Phosphorus oxychloride 2 A' 308 490 182 0.629
OPCl Phosphorus oxychloride 3 A' 492 297 -195 1.654
H2OH2O water dimer 8 A' 103 158 55 0.650
H2OH2O water dimer 11 A" 108 164 56 0.658
H2OH2O water dimer 12 A" 88 137 49 0.641
F3- trifluoride anion 2 Σu 550 432 -118 1.273
H2POH Phosphinous acid 9 A" 375 266 -109 1.409
CHFCl Chlorofluoromethyl radical 6 A 540 390 -150 1.384
ZnCH3 Zinc monomethyl 6 E 315 580 265 0.543
NH2NN+ hydrazoic acid, protonated 6 A' 489 127 -362 3.860
H2CNCN cyanamide, methylene 3 A' 2208 2962 754 0.745
H2CNCN cyanamide, methylene 4 A' 1621 2244 623 0.723
C2H3NO Nitrosoethylene 11 A' 490 339 -151 1.447
SNO Nitrogen oxide sulfide 3 A' 792 494 -299 1.605
AlNC Aluminum isocyanide 3 Π 100 167 67 0.598