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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=FULL/daug-cc-pVDZ
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 298 98 0.670
C2H2 Acetylene 4 Πg 612 450 -162 1.361
CH3CCH propyne 10 E 328 270 -58 1.215
C3O2 Carbon suboxide 7 Πu 61 -58 -119 -1.055
HCNO fulminic acid 5 torsion Π 224 -341 -565 -0.657
CO+ carbon monoxide cation 1 Σ 2184 2856 672 0.765
CH3Li methyl lithium 6 E 409 203 -206 2.017
CH2NH+ Methanimine cation 4 A' 1370 1893 523 0.724
CN Cyano radical 1 Σ 2042 2840 798 0.719
CH2Cl chloromethyl radical 4 B1 402 -156 -558 -2.583
HNC+ hydrogen isocyanide cation 2 Σ 2195 2795 600 0.785
HN3+ Hydrazoic acid cation 2 A' 1850 3329 1479 0.556
HOCl+ hypochlorous acid cation 3 A' 830 1292 462 0.642
NO Nitric oxide 1 Σ 1876 3638 1762 0.516
NO2 Nitrogen dioxide 3 B2 1618 2573 955 0.629
BCl3+ Boron Trichloride cation 3 E' 1104 1543 440 0.715
GaO Gallium monoxide 1 Σ 755 590 -165 1.279
NaO2 Sodium superoxide 3 B2 333 969 636 0.343
SiC2 Silicon dicarbide 3 B2 196 -143 -339 -1.374
LiO2 Lithium dioxide 3 B2 509 1322 813 0.385
C4 Carbon tetramer 4 Πg 323 -166 -489 -1.946
C4 Carbon tetramer 5 Πu 160 131 -29 1.218
SiH2D2 silane-d2 6 B1 2183 1658 -525 1.317
SiH2D2 silane-d2 8 B2 1601 2294 693 0.698
NH4 Ammonium radical 1 A1 2552 3021 469 0.845
GeF Germanium monofluoride 1 Σ 809 647 -162 1.250
BrO+ Bromine monoxide cation 1 Σ 840 1253 413 0.670
CHFCl Chlorofluoromethyl radical 6 A 540 407 -133 1.327
H2CNCN cyanamide, methylene 3 A' 2208 3123 915 0.707
H2CNCN cyanamide, methylene 4 A' 1621 2145 524 0.756
SNO Nitrogen oxide sulfide 3 A' 792 539 -253 1.469
ONNO NO dimer 2 A1 239 347 108 0.690
ONNO NO dimer 3 A1 135 320 185 0.420
ONNO NO dimer 4 torsion A2 117 282 165 0.415
ONNO NO dimer 6 B2 429 615 186 0.697