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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/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" 200 293 93 0.681
C2H2+ acetylene cation 4 Πg 572 818 246 0.699
HCN+ hydrogen cyanide cation 1 Σ 3050 3509 459 0.869
HCN+ hydrogen cyanide cation 2 Σ 1800 2722 922 0.661
CH3CH2CH2CH3 Butane 5 Ag 1442 433 -1009 3.330
CH3CH2CH2CH3 Butane 8 Ag 1151 864 -287 1.331
CH3CH2CH2CH3 Butane 36 Bu 271 3159 2888 0.086
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 1072 -319 1.298
CH2FCH2CH3 1-Fluoropropane 22 A" 890 1303 413 0.683
C3O2 Carbon suboxide 7 Πu 61 -59 -120 -1.028
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 706 -2373 4.359
CO+ carbon monoxide cation 1 Σ 2184 2727 543 0.801
H2CS- thioformaldehyde anion 4 B1 450 340 -110 1.323
LiOH lithium hydroxide 1 Σ 3688 4161 473 0.886
LiOH lithium hydroxide 3 Π 257 435 179 0.589
CH2NH+ Methanimine cation 4 A' 1370 1869 499 0.733
CN Cyano radical 1 Σ 2042 2708 665 0.754
HOCO Hydrocarboxyl radical 1 A' 3316 3791 475 0.875
CH2Cl chloromethyl radical 4 B1 402 142 -260 2.828
HNC+ hydrogen isocyanide cation 2 Σ 2195 2714 519 0.809
HN3+ Hydrazoic acid cation 2 A' 1850 2886 1036 0.641
CaBr2 Calcium dibromide 3 Πu 72 42 -30 1.702
NO Nitric oxide 1 Σ 1876 2526 650 0.743
AsSe Arsenic monoselenide 1 Σ 280 443 163 0.633
C3 carbon trimer 3 Πu 63 94 31 0.672
S3 Sulfur trimer 2 A1 281 621 340 0.452
SiH2D2 silane-d2 6 B1 2183 1652 -531 1.322
SiH2D2 silane-d2 8 B2 1601 2285 684 0.701
NH4 Ammonium radical 1 A1 2552 3156 604 0.809
B5H9 pentaborane9 13 B1 240 625 385 0.384
B5H9 pentaborane9 16 B2 1036 830 -206 1.248
B5H9 pentaborane9 18 B2 600 498 -102 1.206
B5H9 pentaborane9 22 E 1409 1103 -306 1.277
OPCl Phosphorus oxychloride 2 A' 308 521 213 0.592
OPCl Phosphorus oxychloride 3 A' 492 322 -170 1.526
CHFCl Chlorofluoromethyl radical 6 A 540 424 -116 1.272
H2CNCN cyanamide, methylene 3 A' 2208 3147 939 0.702
H2CNCN cyanamide, methylene 4 A' 1621 2409 788 0.673
SNO Nitrogen oxide sulfide 3 A' 792 520 -273 1.524
ONNO NO dimer 3 A1 135 280 145 0.481
ONNO NO dimer 4 torsion A2 117 243 126 0.482
ONNO NO dimer 6 B2 429 706 277 0.608