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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/Def2TZVPP
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 304 104 0.658
HCN+ hydrogen cyanide cation 1 Σ 3050 3547 497 0.860
HCN+ hydrogen cyanide cation 2 Σ 1800 2762 962 0.652
CH2I2 Diiodomethane 3 A1 704 513 -191 1.374
CH2I2 Diiodomethane 4 A1 285 122 -163 2.343
CH2I2 Diiodomethane 7 B1 896 738 -158 1.214
CH3CH2CH2CH3 Butane 5 Ag 1442 427 -1015 3.377
CH3CH2CH2CH3 Butane 8 Ag 1151 859 -292 1.341
CH3CH2CH2CH3 Butane 30 Bu 1461 3074 1613 0.475
CH3CH2CH2CH3 Butane 36 Bu 271 3152 2881 0.086
CHSNH2 thioformamide 12 A" 393 310 -83 1.266
C3F6 hexafluoropropene 21 A" 60 40 -20 1.519
C3O2 Carbon suboxide 7 Πu 61 -54 -115 -1.126
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 714 -2365 4.313
CO+ carbon monoxide cation 1 Σ 2184 2725 541 0.801
H2CS- thioformaldehyde anion 4 B1 450 266 -184 1.690
LiOH lithium hydroxide 1 Σ 3688 4134 446 0.892
CH2NH+ Methanimine cation 4 A' 1370 1871 501 0.732
CN Cyano radical 1 Σ 2042 2711 669 0.753
HOCO Hydrocarboxyl radical 1 A' 3316 3777 461 0.878
CH2Cl chloromethyl radical 4 B1 402 134 -268 2.990
HNC+ hydrogen isocyanide cation 2 Σ 2195 2717 522 0.808
HN3+ Hydrazoic acid cation 2 A' 1850 2920 1070 0.634
CaBr2 Calcium dibromide 3 Πu 72 41 -31 1.748
NO Nitric oxide 1 Σ 1876 2589 713 0.725
BCl3+ Boron Trichloride cation 3 E' 1104 1506 402 0.733
C3 carbon trimer 3 Πu 63 105 42 0.603
S3 Sulfur trimer 2 A1 281 620 339 0.454
NI3 Nitrogen triiodide 3 E 354 647 293 0.547
SiH2D2 silane-d2 6 B1 2183 1655 -528 1.319
SiH2D2 silane-d2 8 B2 1601 2290 689 0.699
CrH Chromium hydride 1 Σ 1534 1979 445 0.775
NH4 Ammonium radical 1 A1 2552 2984 432 0.855
OPCl Phosphorus oxychloride 2 A' 308 521 213 0.591
OPCl Phosphorus oxychloride 3 A' 492 324 -168 1.518
CHFCl Chlorofluoromethyl radical 6 A 540 420 -120 1.287
H2CNCN cyanamide, methylene 3 A' 2208 3140 932 0.703
H2CNCN cyanamide, methylene 4 A' 1621 2404 783 0.674
SNO Nitrogen oxide sulfide 3 A' 792 519 -273 1.526
ONNO NO dimer 3 A1 135 306 171 0.440
ONNO NO dimer 4 torsion A2 117 237 120 0.493
ONNO NO dimer 6 B2 429 709 280 0.605
INO Nitrosyl iodide 2 A' 216 531 315 0.406
INO Nitrosyl iodide 3 A' 470 251 -219 1.870