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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/daug-cc-pVTZ
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 290 90 0.689
C3O2 Carbon suboxide 7 Πu 61 -62 -123 -0.987
HCNO fulminic acid 5 torsion Π 224 -311 -535 -0.720
CO+ carbon monoxide cation 1 Σ 2184 2876 692 0.759
CH2NH+ Methanimine cation 4 A' 1370 1894 524 0.723
CN Cyano radical 1 Σ 2042 2897 854 0.705
CH3 Methyl radical 2 torsion A2" 606 484 -123 1.254
CH2Cl chloromethyl radical 4 B1 402 -157 -559 -2.559
HNC+ hydrogen isocyanide cation 2 Σ 2195 2826 631 0.777
NO Nitric oxide 1 Σ 1876 3335 1459 0.563
NO2 Nitrogen dioxide 3 B2 1618 4444 2826 0.364
GaO Gallium monoxide 1 Σ 755 604 -151 1.249
LiO2 Lithium dioxide 3 B2 509 1010 501 0.504
SiH2D2 silane-d2 6 B1 2183 1659 -524 1.316
SiH2D2 silane-d2 8 B2 1601 2296 695 0.697
NH4 Ammonium radical 1 A1 2552 3048 496 0.837
GeF Germanium monofluoride 1 Σ 809 672 -137 1.203
BrO+ Bromine monoxide cation 1 Σ 840 1264 424 0.664
CHFCl Chlorofluoromethyl radical 6 A 540 414 -126 1.306
H2CNCN cyanamide, methylene 3 A' 2208 3116 908 0.709
H2CNCN cyanamide, methylene 4 A' 1621 2166 545 0.748
SNO Nitrogen oxide sulfide 3 A' 792 536 -256 1.478
ONNO NO dimer 3 A1 135 331 197 0.406
ONNO NO dimer 4 torsion A2 117 284 167 0.412
ONNO NO dimer 6 B2 429 638 208 0.673