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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 MP3/6-311+G(3df,2p)
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 292 92 0.685
HCN+ hydrogen cyanide cation 1 Σ 3050 3528 478 0.865
HCN+ hydrogen cyanide cation 2 Σ 1800 2742 942 0.657
CH3CH2CH2CH3 Butane 5 Ag 1442 430 -1012 3.353
CH3CH2CH2CH3 Butane 8 Ag 1151 860 -291 1.339
CH3CH2CH2CH3 Butane 36 Bu 271 3148 2877 0.086
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 1065 -326 1.306
CH2FCH2CH3 1-Fluoropropane 22 A" 890 1299 409 0.685
C3O2 Carbon suboxide 7 Πu 61 -77 -138 -0.789
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 699 -2379 4.403
CO+ carbon monoxide cation 1 Σ 2184 2726 542 0.801
C6H6 Benzvalene 10 A1 996 787 -209 1.266
H2CS- thioformaldehyde anion 4 B1 450 324 -126 1.389
LiOH lithium hydroxide 1 Σ 3688 4153 465 0.888
LiOH lithium hydroxide 3 Π 257 397 140 0.647
CH2NH+ Methanimine cation 4 A' 1370 1866 496 0.734
CN Cyano radical 1 Σ 2042 2703 660 0.756
HOCO Hydrocarboxyl radical 1 A' 3316 3788 472 0.875
CH2Cl chloromethyl radical 4 B1 402 73 -329 5.518
HNC+ hydrogen isocyanide cation 2 Σ 2195 2710 515 0.810
HN3+ Hydrazoic acid cation 2 A' 1850 2909 1059 0.636
CaBr2 Calcium dibromide 3 Πu 72 40 -32 1.800
NO Nitric oxide 1 Σ 1876 2562 686 0.732
BCl3+ Boron Trichloride cation 3 E' 1104 1504 400 0.734
AsSe Arsenic monoselenide 1 Σ 280 436 156 0.642
S3 Sulfur trimer 2 A1 281 620 339 0.453
SiH2D2 silane-d2 6 B1 2183 1647 -536 1.326
SiH2D2 silane-d2 8 B2 1601 2278 677 0.703
NH4 Ammonium radical 1 A1 2552 3141 589 0.812
N2H2+ trans-diazene cation 3 Ag 1180 513 -667 2.299
OPCl Phosphorus oxychloride 2 A' 308 518 210 0.595
OPCl Phosphorus oxychloride 3 A' 492 321 -171 1.531
CHFCl Chlorofluoromethyl radical 6 A 540 421 -119 1.281
H2CNCN cyanamide, methylene 3 A' 2208 3136 928 0.704
H2CNCN cyanamide, methylene 4 A' 1621 2398 777 0.676
SNO Nitrogen oxide sulfide 3 A' 792 520 -272 1.523
ONNO NO dimer 3 A1 135 278 144 0.484
ONNO NO dimer 4 torsion A2 117 241 124 0.485
ONNO NO dimer 6 B2 429 703 274 0.611