return to home page Computational Chemistry Comparison and Benchmark DataBase Release 18 (October 2016) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Calculated > Vibrations > Bad Calculations > Bad vib. Calc. vs exp. OR Resources > Bad Calculations > Vibrations > Bad vib. Calc. vs exp.

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/aug-cc-pVQZ
Calculated values were scaled by 0.9085.

Species Name mode Symmetry Experiment Theory difference ratio
C2H4+ Ethylene cation 4 Au 84 348 264 0.242
CHONH2 formamide 12 A" 289 196 -93 1.475
C2H2N4 sym-tetrazine 18 B3u 254 369 115 0.687
C2H Ethynyl radical 3 Π 372 555 184 0.669
C2H+ Ethynyl cation 3 Π 550 855 306 0.643
CH3 Methyl radical 2 A2" 606 377 -229 1.607
CH2OH Hydroxymethyl radical 8 A 482 693 211 0.695
CH2OH Hydroxymethyl radical 9 A 234 365 131 0.642
C2H3+ vinyl cation 2 A1 2217 2893 676 0.766
NS Mononitrogen monosulfide 1 Σ 1219 851 -367 1.432
VO Vanadium monoxide 1 Σ 1011 528 -484 1.916
SiP Silicon monophosphide 1 Σ 616 430 -186 1.432
PS phosphorus sulfide 1 Σ 739 495 -244 1.493
BH3CO Borane carbonyl 4 A1 691 508 -183 1.361
AlO Aluminum monoxide 1 Σ 979 727 -252 1.347
C2H4O4 Formic acid dimer 13 Au 1050 68 -982 15.441
C2H4O4 Formic acid dimer 24 Bu 268 197 -71 1.359
PN+ phosphorus nitride cation 1 Σ 1200 764 -436 1.571
H2POH Phosphinous acid 9 A" 375 260 -115 1.444
Mg2 Magnesium diatomic 1 Σg 51 2 -49 20.755
NNS Nitrogen sulfide 2 Σ 752 551 -201 1.366
CH3BO Borane, methyloxo- 7 E 897 1428 531 0.628