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 MP3=FULL/Def2TZVPP
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 303 103 0.660
C2H2+ acetylene cation 4 Πg 572 821 249 0.697
HCN+ hydrogen cyanide cation 1 Σ 3050 3515 465 0.868
HCN+ hydrogen cyanide cation 2 Σ 1800 2740 940 0.657
CH2I2 Diiodomethane 3 A1 704 513 -191 1.371
CH2I2 Diiodomethane 4 A1 285 122 -163 2.338
CH2I2 Diiodomethane 7 B1 896 733 -163 1.223
CHSNH2 thioformamide 12 A" 393 317 -76 1.239
C3F6 hexafluoropropene 21 A" 60 40 -20 1.491
C3O2 Carbon suboxide 7 Πu 61 38 -23 1.621
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 724 -2354 4.250
CO+ carbon monoxide cation 1 Σ 2184 2728 544 0.801
H2CS- thioformaldehyde anion 4 B1 450 288 -162 1.563
LiOH lithium hydroxide 1 Σ 3688 4132 444 0.892
CH2NH+ Methanimine cation 4 A' 1370 1872 502 0.732
CN Cyano radical 1 Σ 2042 2717 675 0.752
HOCO Hydrocarboxyl radical 1 A' 3316 3774 458 0.879
CH2Cl chloromethyl radical 4 B1 402 181 -221 2.216
HNC+ hydrogen isocyanide cation 2 Σ 2195 2721 526 0.807
HN3+ Hydrazoic acid cation 2 A' 1850 2909 1059 0.636
CaBr2 Calcium dibromide 3 Πu 72 41 -31 1.762
NO Nitric oxide 1 Σ 1876 2556 680 0.734
C3 carbon trimer 3 Πu 63 129 66 0.491
S3 Sulfur trimer 2 A1 281 621 340 0.453
NI3 Nitrogen triiodide 3 E 354 652 298 0.543
SiH2D2 silane-d2 6 B1 2183 1665 -518 1.311
SiH2D2 silane-d2 8 B2 1601 2304 703 0.695
NH4 Ammonium radical 1 A1 2552 2984 432 0.855
OPCl Phosphorus oxychloride 2 A' 308 522 214 0.590
OPCl Phosphorus oxychloride 3 A' 492 324 -168 1.517
CHFCl Chlorofluoromethyl radical 6 A 540 421 -119 1.284
H2CNCN cyanamide, methylene 3 A' 2208 3139 931 0.703
H2CNCN cyanamide, methylene 4 A' 1621 2410 789 0.673
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 117 238 121 0.491
ONNO NO dimer 6 B2 429 715 286 0.600
INO Nitrosyl iodide 2 A' 216 532 316 0.406
INO Nitrosyl iodide 3 A' 470 252 -218 1.867