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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-pVQZ
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 298 98 0.671
CH3CHO+ acetaldehyde cation 15 A" 145 66 -79 2.180
CH3SCH3+ dimethyl sulfide cation 15 B1 172 129 -43 1.332
CH3CH2CH2CH3 Butane 5 Ag 1442 435 -1007 3.318
CH3CH2CH2CH3 Butane 8 Ag 1151 851 -300 1.352
CH3CH2CH2CH3 Butane 25 Bg 803 1506 703 0.533
CH3CH2CH2CH3 Butane 36 Bu 271 3117 2846 0.087
CH3CHFCH3 2-Fluoropropane 27 A" 243 191 -52 1.269
C3O2 Carbon suboxide 7 Πu 61 -31 -92 -1.958
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 695 -2384 4.428
H2CS- thioformaldehyde anion 4 B1 450 261 -189 1.725
CFCl2 dichlorofluoromethyl radical 2 A' 747 605 -142 1.235
CH2Cl chloromethyl radical 4 B1 402 206 -196 1.951
BCl3+ Boron Trichloride cation 3 E' 1104 783 -321 1.410
AsSe Arsenic monoselenide 1 Σ 280 432 152 0.648
SiC2 Silicon dicarbide 3 B2 196 161 -35 1.218
C3 carbon trimer 3 Πu 63 27 -37 2.358
S3 Sulfur trimer 2 A1 281 631 350 0.446
SiH2D2 silane-d2 6 B1 2183 1607 -576 1.358
SiH2D2 silane-d2 8 B2 1601 2224 623 0.720
Br3- tribromide anion 2 Σu 214 148 -66 1.447
B5H9 pentaborane9 13 B1 240 614 374 0.391
B5H9 pentaborane9 16 B2 1036 823 -213 1.259
B5H9 pentaborane9 22 E 1409 1088 -321 1.296
OPCl Phosphorus oxychloride 2 A' 308 513 205 0.600
OPCl Phosphorus oxychloride 3 A' 492 315 -177 1.563
H2OH2O water dimer 8 A' 103 166 63 0.620
H2OH2O water dimer 11 A" 108 162 54 0.668
H2OH2O water dimer 12 A" 88 140 52 0.628
CHFCl Chlorofluoromethyl radical 6 A 540 413 -127 1.307
NH2NN+ hydrazoic acid, protonated 6 A' 489 338 -151 1.445
H2CNCN cyanamide, methylene 3 A' 2208 3087 879 0.715
H2CNCN cyanamide, methylene 4 A' 1621 2353 732 0.689
C2H3NO Nitrosoethylene 11 A' 490 357 -133 1.373
SNO Nitrogen oxide sulfide 3 A' 792 515 -277 1.538
ONNO NO dimer 2 A1 239 421 182 0.569
ONNO NO dimer 3 A1 135 364 230 0.369
ONNO NO dimer 4 torsion A2 117 227 110 0.516
ONNO NO dimer 6 B2 429 782 353 0.549