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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 B3LYP/aug-cc-pVTZ
Calculated values were scaled by 0.9675.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 180 67 0.628
C4H10O Ethoxy ethane 12 A1 240 188 -52 1.278
C4H10O Ethoxy ethane 20 A2 137 102 -35 1.344
CH3CONH2 Acetamide 20 A 259 203 -55 1.272
CH3COOH Acetic acid 18 torsion A" 93 65 -28 1.422
C2H6O2S Dimethyl sulfone 20 B1 262 200 -62 1.311
C2H4+ Ethylene cation 4 torsion Au 84 -498 -582 -0.169
CH3SCH3+ dimethyl sulfide cation 15 B1 172 121 -51 1.419
CH3COCl Acetyl Chloride 15 torsion A" 166 125 -41 1.323
C3F8 perfluoropropane 13 A2 276 218 -58 1.268
CH3COCH2CH3 2-Butanone 33 torsion A" 87 -36 -123 -2.437
CH3COOCH3 methyl acetate 27 torsion A" 110 39 -71 2.854
CH2BrCH2Br Ethane, 1,2-dibromo- 10 A 91 73 -18 1.252
CH3CH2CH2CH3 Butane 5 Ag 1442 410 -1032 3.515
CH3CH2CH2CH3 Butane 8 Ag 1151 811 -340 1.419
CH3CH2CH2CH3 Butane 30 Bu 1461 2921 1460 0.500
CH3CH2CH2CH3 Butane 36 Bu 271 2982 2711 0.091
C3H6O 2-Propen-1-ol 23 A 277 218 -59 1.272
C3H6O 2-Propen-1-ol 24 A 188 111 -77 1.695
CH2ClCHO chloroacetaldehyde 15 torsion A 27 50 23 0.544
C3F6 hexafluoropropene 21 A" 60 37 -23 1.602
C5H8 Cyclopentene 18 torsion A' 254 130 -124 1.950
C4H6O2 2,3-Butanedione 21 torsion Bg 240 114 -126 2.101
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 985 -406 1.413
C5H12 Propane, 2,2-dimethyl- 12 T1 203 298 95 0.681
C3H6O Oxetane 18 B1 90 41 -48 2.164
C3H6O Oxetane 23 B2 1228 989 -239 1.242
CH3OC2H5 Ethane, methoxy- 29 A" 248 198 -50 1.253
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 664 -2415 4.638
C5H8 1,4-Pentadiene 16 A 137 293 156 0.467
C5H8 1,4-Pentadiene 33 torsion B 331 101 -230 3.262
P(CH3)3 trimethylphosphine 22 E 259 201 -58 1.290
C6H6 Benzvalene 10 A1 996 742 -254 1.343
H2CS- thioformaldehyde anion 4 B1 450 290 -160 1.550
NaOH sodium hydroxide 3 torsion Π 300 146 -154 2.061
SiF2+ Silicon difluoride cation 2 A1 350 273 -77 1.284
CFCl2 dichlorofluoromethyl radical 2 A' 747 566 -181 1.319
CH3OO methylperoxy radical 12 torsion A" 170 120 -50 1.412
C4H9N Cyclobutylamine 21 A' 174 134 -40 1.301
CH2OH Hydroxymethyl radical 9 torsion A 234 395 161 0.592
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 867 -269 1.310
C6H8 (Z)-hexa-1,3,5-triene 19 torsion A2 264 145 -119 1.815
C6H8 (Z)-hexa-1,3,5-triene 24 torsion B1 358 100 -258 3.571
HCCN cyanomethylene 5 Π 129 -216 -345 -0.596
CHCl2 dichloromethyl radical 4 A' 190 290 100 0.655
C4H6 Methylenecyclopropane 17 B1 360 285 -75 1.264
CH2Cl chloromethyl radical 4 B1 402 188 -214 2.140
BF3+ boron trifluoride cation 5 B2 1791 734 -1056 2.438
BCl3+ Boron Trichloride cation 3 E' 1104 780 -323 1.414
N2O3 Dinitrogen trioxide 9 torsion A" 63 134 71 0.469
SiC2 Silicon dicarbide 3 B2 196 92 -104 2.129
C3 carbon trimer 3 Πu 63 98 35 0.645
S3 Sulfur trimer 2 A1 281 570 289 0.493
SiH2D2 silane-d2 6 B1 2183 1563 -620 1.396
SiH2D2 silane-d2 8 B2 1601 2163 562 0.740
Br3- tribromide anion 2 Σu 214 170 -44 1.261
GeF Germanium monofluoride 1 Σ 809 617 -192 1.312
ClOO chloroperoxy radical 2 A' 414 311 -102 1.329
ClOO chloroperoxy radical 3 A' 201 108 -94 1.868
B4H10 Tetraborane(10) 10 A1 827 653 -174 1.266
B4H10 Tetraborane(10) 11 A1 785 542 -243 1.449
B4H10 Tetraborane(10) 12 A1 559 207 -352 2.695
B4H10 Tetraborane(10) 19 A2 662 406 -256 1.632
B4H10 Tetraborane(10) 36 B2 236 348 112 0.678
Cl3- trichloride anion 2 Σu 327 246 -81 1.332
B5H9 pentaborane9 13 B1 240 605 365 0.397
B5H9 pentaborane9 16 B2 1036 786 -250 1.318
B5H9 pentaborane9 18 B2 600 460 -140 1.306
B5H9 pentaborane9 22 E 1409 1049 -360 1.343
OPCl Phosphorus oxychloride 2 A' 308 464 156 0.664
OPCl Phosphorus oxychloride 3 A' 492 287 -205 1.713
H2OH2O water dimer 8 A' 103 154 51 0.669
F3- trifluoride anion 2 Σu 550 427 -123 1.288
H2POH Phosphinous acid 9 A" 375 255 -121 1.474
CHFCl Chlorofluoromethyl radical 6 A 540 391 -149 1.382
NH2NN+ hydrazoic acid, protonated 6 A' 489 338 -151 1.447
H2CNCN cyanamide, methylene 3 A' 2208 2965 757 0.745
H2CNCN cyanamide, methylene 4 A' 1621 2224 603 0.729
C2H3NO Nitrosoethylene 11 A' 490 343 -147 1.431
SNO Nitrogen oxide sulfide 3 A' 792 493 -299 1.607
ONNO NO dimer 2 A1 239 395 156 0.606
ONNO NO dimer 3 A1 135 282 148 0.477
ONNO NO dimer 4 torsion A2 117 224 107 0.521
ONNO NO dimer 6 B2 429 699 270 0.614