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
CH3CHO+ acetaldehyde cation 15 A" 145 67 -78 2.172
CH3COCl Acetyl Chloride 15 torsion A" 166 128 -38 1.294
CH3COCH2CH3 2-Butanone 32 torsion A" 106 -41 -147 -2.607
CH3COCH2CH3 2-Butanone 33 torsion A" 87 -126 -213 -0.689
C2Br4 tetrabromoethene 7 B2g 464 993 529 0.467
C3F6 hexafluoropropene 21 A" 60 24 -36 2.481
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
C5H8 Cyclopentene 18 torsion A' 254 155 -99 1.640
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
C4H9N Pyrrolidine 36 A" 65 94 29 0.689
HCNO fulminic acid 5 torsion Π 224 339 115 0.662
CH2C(CH3)CH3 1-Propene, 2-methyl- 15 torsion A2 193 130 -63 1.480
CH3OC2H5 Ethane, methoxy- 29 A" 248 187 -61 1.329
C5H12 Pentane 23 A2 131 82 -49 1.590
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
CH2ClCHO chloroacetaldehyde 15 A" 59 139 80 0.424
CH2ClCHO chloroacetaldehyde 15 torsion A 27 54 27 0.503
C3H6O 2-Propen-1-ol 24 A 188 110 -78 1.713
CH2BrCH2Br Ethane, 1,2-dibromo- 10 A 91 70 -21 1.309
C6H4Cl2 1,4-dichlorobenzene 30 B3u 122 96 -26 1.268
C6H6 Benzvalene 10 A1 996 744 -252 1.339
CH3COOCH3 methyl acetate 27 torsion A" 110 -120 -230 -0.914
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 29 -46 2.596
C3F8 perfluoropropane 13 A2 276 217 -59 1.271
CH3SCH3+ dimethyl sulfide cation 15 B1 172 118 -54 1.463
C2H4+ Ethylene cation 4 torsion Au 84 -410 -494 -0.205
C2H+ Ethynyl cation 3 Π 550 940 390 0.585
CH3OO methylperoxy radical 12 torsion A" 170 111 -59 1.536
CH3OH Methyl alcohol 12 torsion A" 200 304 104 0.658
CH2OH Hydroxymethyl radical 9 torsion A 234 407 173 0.576
CH3COOH Acetic acid 18 torsion A" 93 -107 -200 -0.871
HCCN cyanomethylene 5 Π 129 -300 -429 -0.429
C4H10O Ethoxy ethane 20 A2 137 71 -66 1.936
CHCl2 dichloromethyl radical 4 A' 190 295 105 0.643
CH3CSCH3 Thioacetone 17 B1 153 120 -33 1.273
CH3CHFCH3 2-Fluoropropane 27 A" 243 190 -53 1.280
C4H6 Methylenecyclopropane 17 B1 360 279 -81 1.290
C6H4 Benzyne 24 B2 472 374 -98 1.262
CH2Cl chloromethyl radical 4 B1 402 182 -220 2.207
C3H6O Oxetane 18 B1 90 -76 -165 -1.187
C3O2 Carbon suboxide 7 Πu 61 154 93 0.395
CH3COF Acetyl fluoride 15 torsion A" 123 -51 -174 -2.433
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 679 -2400 4.535
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
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
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
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
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
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
ClOO chloroperoxy radical 2 A' 414 218 -196 1.897
ClOO chloroperoxy radical 3 A' 201 107 -95 1.891
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
CHFCl Chlorofluoromethyl radical 6 A 540 390 -150 1.384
ZnCH3 Zinc monomethyl 6 E 315 580 265 0.543
H2CNCN cyanamide, methylene 3 A' 2208 2962 754 0.745
H2CNCN cyanamide, methylene 4 A' 1621 2244 623 0.723
SNO Nitrogen oxide sulfide 3 A' 792 494 -299 1.605
AlNC Aluminum isocyanide 3 Π 100 167 67 0.598
SiH2D2 silane-d2 6 B1 2183 1529 -654 1.428
SiH2D2 silane-d2 8 B2 1601 2116 515 0.757
C3O Tricarbon monoxide 5 Π 109 186 77 0.586
H2POH Phosphinous acid 9 A" 375 266 -109 1.409
NH2NN+ hydrazoic acid, protonated 6 A' 489 127 -362 3.860
C2H3NO Nitrosoethylene 11 A' 490 339 -151 1.447