return to home page Computational Chemistry Comparison and Benchmark DataBase Release 18 (October 2016) Standard Reference Database 101 National Institute of Standards and Technology
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Bad vibrational frequency predictions

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 HF/cc-pVQZ
Calculated values were scaled by 0.9084.

Species Name mode Symmetry Experiment Theory difference ratio
C2H4+ Ethylene cation 4 Au 84 352 268 0.239
CHONH2 formamide 12 A" 289 173 -116 1.673
C2H2N4 sym-tetrazine 18 B3u 254 370 116 0.686
NH2CN cyanamide 5 A' 408 614 206 0.665
C6H4 Benzyne 24 B2 472 299 -173 1.580
HCNO fulminic acid 5 Π 224 548 324 0.409
CH3NC methyl isocyanide 8 E 263 386 123 0.682
C2H Ethynyl radical 3 Π 372 555 184 0.669
C2H+ Ethynyl cation 3 Π 550 855 305 0.643
CH3 Methyl radical 2 A2" 606 373 -233 1.626
CH2OH Hydroxymethyl radical 8 A 482 699 217 0.689
CH2OH Hydroxymethyl radical 9 A 234 363 129 0.645
ClCO carbonyl monochloride 3 A' 335 247 -87 1.353
C2H3+ vinyl cation 2 A1 2217 2892 675 0.766
CH3CO Acetyl radical 4 A' 1420 2957 1537 0.480
FOOF Perfluoroperoxide 2 A 630 1043 413 0.604
FOOF Perfluoroperoxide 3 A 360 520 160 0.693
FOOF Perfluoroperoxide 5 B 614 1036 422 0.593
NS Mononitrogen monosulfide 1 Σ 1219 851 -368 1.432
VO Vanadium monoxide 1 Σ 1011 530 -482 1.910
SiP Silicon monophosphide 1 Σ 616 430 -186 1.433
PS phosphorus sulfide 1 Σ 739 495 -245 1.494
BH3CO Borane carbonyl 4 A1 691 507 -184 1.362
SO+ sulfur monoxide cation 1 Σ 1360 888 -472 1.531
AlO Aluminum monoxide 1 Σ 979 730 -249 1.341
C2H4O4 Formic acid dimer 13 Au 1050 68 -982 15.492
C2H4O4 Formic acid dimer 24 Bu 268 198 -70 1.353
ClOO chloroperoxy radical 2 A' 414 705 291 0.587
ClOO chloroperoxy radical 3 A' 201 436 235 0.462
PN+ phosphorus nitride cation 1 Σ 1200 764 -436 1.570
H2POH Phosphinous acid 9 A" 375 262 -113 1.430
Mg2 Magnesium diatomic 1 Σg 51 2 -49 20.771
NNS Nitrogen sulfide 2 Σ 752 551 -201 1.365
CH3BO Borane, methyloxo- 7 E 897 1428 531 0.628