return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Calculated > Vibrations > Bad Calculations > Bad vib. Calc. vs exp. OR Resources > Bad Calculations > Vibrations > Bad vib. Calc. vs exp.

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/cc-pVTZ
Calculated values were scaled by 0.9666.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 182 69 0.622
C4H10O Ethoxy ethane 12 A1 240 187 -53 1.284
C4H10O Ethoxy ethane 20 A2 137 101 -36 1.355
CH3COOH Acetic acid 18 torsion A" 93 75 -18 1.246
CH3OH Methyl alcohol 12 torsion A" 200 290 90 0.690
C2H6O2S Dimethyl sulfone 20 B1 262 199 -63 1.315
C2H4+ Ethylene cation 4 torsion Au 84 -483 -567 -0.174
CHONH2 formamide 12 torsion A" 289 204 -85 1.417
CH3SCH3+ dimethyl sulfide cation 15 B1 172 118 -54 1.453
CH3COCl Acetyl Chloride 15 torsion A" 166 128 -38 1.301
C3F8 perfluoropropane 13 A2 276 217 -59 1.269
CH3COOCH3 methyl acetate 27 torsion A" 110 44 -66 2.521
CH2BrCH2Br Ethane, 1,2-dibromo- 10 A 91 73 -18 1.248
CH3CH2CH2CH3 Butane 5 Ag 1442 410 -1032 3.518
CH3CH2CH2CH3 Butane 8 Ag 1151 811 -340 1.420
CH3CH2CH2CH3 Butane 30 Bu 1461 2920 1459 0.500
CH3CH2CH2CH3 Butane 36 Bu 271 2981 2710 0.091
C3H6O 2-Propen-1-ol 23 A 277 218 -59 1.272
C3H6O 2-Propen-1-ol 24 A 188 111 -77 1.688
CH2ClCHO chloroacetaldehyde 15 torsion A 27 53 26 0.510
CH2ClCHO chloroacetaldehyde 15 A" 59 167 108 0.352
C3F6 hexafluoropropene 21 A" 60 36 -24 1.688
C5H8 Cyclopentene 18 torsion A' 254 130 -124 1.959
C4H6O2 2,3-Butanedione 21 torsion Bg 240 112 -128 2.142
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 991 -400 1.403
C5H12 Propane, 2,2-dimethyl- 12 T1 203 300 97 0.677
C2H3NO3 Oxamic acid 3 A' 2600 3467 867 0.750
C2H3NO3 Oxamic acid 15 A' 328 261 -67 1.257
C2H3NO3 Oxamic acid 17 A" 815 650 -165 1.254
C2H3NO3 Oxamic acid 21 A" 162 63 -99 2.592
C3H6O Oxetane 18 B1 90 58 -32 1.547
CH3OC2H5 Ethane, methoxy- 29 A" 248 199 -49 1.248
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 664 -2415 4.638
C5H8 1,4-Pentadiene 16 A 137 292 155 0.469
P(CH3)3 trimethylphosphine 22 E 259 201 -58 1.291
C6H6 Benzvalene 10 A1 996 743 -253 1.341
H2CS- thioformaldehyde anion 4 B1 450 179 -271 2.510
SiF2+ Silicon difluoride cation 2 A1 350 272 -78 1.285
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 210 66 0.687
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 352 -104 1.295
CFCl2 dichlorofluoromethyl radical 2 A' 747 568 -179 1.316
CH3OO methylperoxy radical 12 torsion A" 170 124 -46 1.374
C4H9N Cyclobutylamine 21 A' 174 139 -35 1.255
CH2OH Hydroxymethyl radical 9 torsion A 234 407 173 0.575
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 866 -270 1.312
C6H8 (Z)-hexa-1,3,5-triene 19 torsion A2 264 150 -114 1.763
C6H8 (Z)-hexa-1,3,5-triene 24 torsion B1 358 101 -257 3.551
HCCN cyanomethylene 5 Π 129 -214 -343 -0.601
CHCl2 dichloromethyl radical 4 A' 190 290 100 0.656
C4H6 Methylenecyclopropane 17 B1 360 285 -75 1.265
CH2Cl chloromethyl radical 4 B1 402 180 -222 2.236
BF3+ boron trifluoride cation 5 B2 1791 735 -1056 2.436
CaBr2 Calcium dibromide 3 Πu 72 23 -49 3.156
BCl3+ Boron Trichloride cation 3 E' 1104 782 -322 1.411
N2O3 Dinitrogen trioxide 9 torsion A" 63 137 74 0.459
SiC2 Silicon dicarbide 3 B2 196 98 -98 1.997
C3 carbon trimer 3 Πu 63 101 38 0.626
S3 Sulfur trimer 2 A1 281 570 289 0.493
Br3- tribromide anion 2 Σu 214 171 -43 1.248
GeF Germanium monofluoride 1 Σ 809 630 -179 1.284
ClOO chloroperoxy radical 2 A' 414 309 -105 1.339
ClOO chloroperoxy radical 3 A' 201 114 -88 1.770
B4H10 Tetraborane(10) 10 A1 827 653 -174 1.266
B4H10 Tetraborane(10) 11 A1 785 541 -244 1.450
B4H10 Tetraborane(10) 12 A1 559 207 -352 2.696
B4H10 Tetraborane(10) 19 A2 662 406 -256 1.632
B4H10 Tetraborane(10) 36 B2 236 349 113 0.677
Cl3- trichloride anion 2 Σu 327 254 -73 1.290
B5H9 pentaborane9 13 B1 240 605 365 0.397
B5H9 pentaborane9 16 B2 1036 786 -250 1.319
B5H9 pentaborane9 18 B2 600 459 -141 1.307
B5H9 pentaborane9 22 E 1409 1049 -360 1.343
OPCl Phosphorus oxychloride 2 A' 308 465 157 0.662
OPCl Phosphorus oxychloride 3 A' 492 288 -204 1.711
H2POH Phosphinous acid 9 A" 375 255 -120 1.469
CHFCl Chlorofluoromethyl radical 6 A 540 390 -150 1.383
NH2NN+ hydrazoic acid, protonated 6 A' 489 315 -174 1.554
H2CNCN cyanamide, methylene 3 A' 2208 2962 754 0.746
H2CNCN cyanamide, methylene 4 A' 1621 2227 606 0.728
C2H3NO Nitrosoethylene 11 A' 490 340 -150 1.440
SNO Nitrogen oxide sulfide 3 A' 792 491 -301 1.612
NSO sulfinyl amidogen 3 A' 300 762 462 0.393