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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 MP2/aug-cc-pVQZ
Calculated values were scaled by 0.9497.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H4+ Ethylene cation 4 torsion Au 84 -157 -242 -0.534
HCN+ hydrogen cyanide cation 1 Σ 3050 3530 480 0.864
HCN+ hydrogen cyanide cation 2 Σ 1800 2704 904 0.666
CHONH2 formamide 12 torsion A" 289 199 -89 1.447
CH3CH2CH2CH3 Butane 5 Ag 1442 403 -1039 3.578
CH3CH2CH2CH3 Butane 20 Bg 2965 1342 -1623 2.210
C3O2 Carbon suboxide 7 Πu 61 45 -16 1.369
HCNO fulminic acid 5 torsion Π 224 -282 -506 -0.794
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 664 -2415 4.636
CO+ carbon monoxide cation 1 Σ 2184 2743 559 0.796
H2CS- thioformaldehyde anion 4 B1 450 328 -122 1.371
CH2NH+ Methanimine cation 4 A' 1370 1806 436 0.758
CN Cyano radical 1 Σ 2042 2771 729 0.737
C2H Ethynyl radical 2 Σ 1841 2413 572 0.763
C2H Ethynyl radical 3 torsion Π 372 787 415 0.472
C2H+ Ethynyl cation 3 Π 550 794 245 0.692
CH3 Methyl radical 2 torsion A2" 606 480 -127 1.264
CH2OH Hydroxymethyl radical 9 torsion A 234 413 179 0.567
HCCN cyanomethylene 5 Π 129 -469 -598 -0.275
CH2Cl chloromethyl radical 4 B1 402 -18 -420 -22.853
HNC+ hydrogen isocyanide cation 2 Σ 2195 2700 504 0.813
O2+ diatomic oxygen cation 1 Σg 1873 1448 -425 1.294
O3 Ozone 3 B2 1042 2100 1058 0.496
NO Nitric oxide 1 Σ 1876 3085 1209 0.608
NO2 Nitrogen dioxide 3 B2 1618 6378 4760 0.254
GaO Gallium monoxide 1 Σ 755 587 -168 1.286
NaO2 Sodium superoxide 3 B2 333 670 337 0.497
VO Vanadium monoxide 1 Σ 1002 2062 1061 0.486
FO Oxygen monofluoride 1 Σ 1033 2522 1489 0.410
C3 carbon trimer 3 Πu 63 143 80 0.442
LiO2 Lithium dioxide 3 B2 509 855 346 0.595
SiP Silicon monophosphide 1 Σ 611 1058 447 0.578
SiH2D2 silane-d2 6 B1 2183 1582 -601 1.380
SiH2D2 silane-d2 8 B2 1601 2189 588 0.731
AlO Aluminum monoxide 1 Σ 965 632 -334 1.528
B5H9 pentaborane9 13 B1 240 583 343 0.412
B5H9 pentaborane9 16 B2 1036 772 -264 1.342
B5H9 pentaborane9 18 B2 600 471 -129 1.273
B5H9 pentaborane9 22 E 1409 1031 -378 1.366
OPCl Phosphorus oxychloride 2 A' 308 482 174 0.639
OPCl Phosphorus oxychloride 3 A' 492 290 -202 1.695
NCO isocyanato radical 1 Σ 1921 2353 432 0.816
H2POH Phosphinous acid 9 A" 375 259 -116 1.448
CHFCl Chlorofluoromethyl radical 6 A 540 396 -144 1.365
H2CNCN cyanamide, methylene 3 A' 2208 2965 757 0.745
H2CNCN cyanamide, methylene 4 A' 1621 2067 446 0.784
SNO Nitrogen oxide sulfide 3 A' 792 512 -280 1.547
ONNO NO dimer 3 A1 135 316 182 0.425
ONNO NO dimer 4 torsion A2 117 273 156 0.428
NSO sulfinyl amidogen 3 A' 300 195 -105 1.540