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/6-31G**
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 337 137 0.593
CH3CHO+ acetaldehyde cation 15 A" 145 66 -79 2.187
CH3SCH3+ dimethyl sulfide cation 15 B1 172 124 -48 1.385
CH3CH2CH2CH3 Butane 5 Ag 1442 435 -1007 3.318
CH3CH2CH2CH3 Butane 8 Ag 1151 855 -296 1.346
CH3CH2CH2CH3 Butane 36 Bu 271 3140 2869 0.086
C3F6 hexafluoropropene 21 A" 60 24 -36 2.537
CH3CH2CHO Propanal 24 torsion A" 135 112 -23 1.206
CF3CHF2 pentafluoroethane 18 torsion A" 75 59 -16 1.272
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 1058 -333 1.314
CH2FCH2CH3 1-Fluoropropane 22 A" 890 1291 401 0.690
C3O2 Carbon suboxide 7 Πu 61 115 54 0.532
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 712 -2367 4.325
C6H6 Benzvalene 10 A1 996 787 -209 1.266
H2CS- thioformaldehyde anion 4 B1 450 24 -426 18.741
LiOH lithium hydroxide 1 Σ 3688 4095 408 0.900
CFCl2 dichlorofluoromethyl radical 2 A' 747 620 -127 1.205
CH3 Methyl radical 2 torsion A2" 606 473 -133 1.282
HOCO Hydrocarboxyl radical 1 A' 3316 3725 409 0.890
CHCl2 dichloromethyl radical 4 A' 190 311 121 0.611
CH2Cl chloromethyl radical 4 B1 402 90 -312 4.468
BeBr2 Beryllium bromide 3 Πu 207 354 147 0.585
BCl3+ Boron Trichloride cation 3 E' 1104 808 -296 1.366
C3O Tricarbon monoxide 5 Π 109 182 73 0.600
AsSe Arsenic monoselenide 1 Σ 280 438 158 0.639
SiC2 Silicon dicarbide 3 B2 196 140 -57 1.405
C3 carbon trimer 3 Πu 63 163 99 0.390
S3 Sulfur trimer 2 A1 281 617 336 0.456
SiH2D2 silane-d2 6 B1 2183 1603 -580 1.362
SiH2D2 silane-d2 8 B2 1601 2218 617 0.722
H3O+ hydronium cation 2 A1 954 779 -175 1.225
B5H9 pentaborane9 13 B1 240 626 386 0.383
B5H9 pentaborane9 16 B2 1036 821 -215 1.261
B5H9 pentaborane9 22 E 1409 1102 -307 1.278
OPCl Phosphorus oxychloride 2 A' 308 519 211 0.593
OPCl Phosphorus oxychloride 3 A' 492 312 -180 1.575
H2OH2O water dimer 6 A' 311 452 141 0.688
H2OH2O water dimer 7 A' 143 223 80 0.640
H2OH2O water dimer 11 A" 108 165 57 0.656
H2OH2O water dimer 12 A" 88 -25 -113 -3.570
CHFCl Chlorofluoromethyl radical 6 A 540 410 -130 1.317
NH2NN+ hydrazoic acid, protonated 6 A' 489 164 -325 2.981
H2CNCN cyanamide, methylene 3 A' 2208 3110 902 0.710
H2CNCN cyanamide, methylene 4 A' 1621 2366 745 0.685
C2H3NO Nitrosoethylene 11 A' 490 349 -141 1.403
SNO Nitrogen oxide sulfide 3 A' 792 519 -273 1.526
ONNO NO dimer 2 A1 239 414 174 0.578
ONNO NO dimer 3 A1 135 374 240 0.359
ONNO NO dimer 4 torsion A2 117 231 114 0.507
ONNO NO dimer 6 B2 429 773 344 0.555
ZnCN Zinc monocyanide 3 Π 212 87 -125 2.448