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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 MP3=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" 200 297 97 0.674
CH3CH2CHO Propanal 5 A' 1743 2974 1231 0.586
CH3CH2CHO Propanal 15 A' 271 672 401 0.403
C4H4Se selenophene 15 B2 3120 781 -2339 3.993
C4H4Se selenophene 16 B2 3052 740 -2312 4.122
C4H4Se selenophene 17 B2 1514 726 -788 2.087
C4H4Se selenophene 18 B2 1248 647 -601 1.929
C4H4Se selenophene 20 B2 825 467 -358 1.768
C4H4Se selenophene 21 B2 625 402 -223 1.556
C3O2 Carbon suboxide 7 Πu 61 -111 -172 -0.549
CO+ carbon monoxide cation 1 Σ 2184 2699 515 0.809
CH3Li methyl lithium 6 E 409 135 -273 3.015
CH2NH+ Methanimine cation 4 A' 1370 1863 493 0.735
CN Cyano radical 1 Σ 2042 2654 611 0.770
HOCO Hydrocarboxyl radical 1 A' 3316 3735 419 0.888
CH2Cl chloromethyl radical 4 B1 402 -119 -521 -3.380
HNC+ hydrogen isocyanide cation 2 Σ 2195 2683 487 0.818
HN3+ Hydrazoic acid cation 2 A' 1850 3028 1178 0.611
HOCl+ hypochlorous acid cation 3 A' 830 1273 443 0.652
NO Nitric oxide 1 Σ 1876 2901 1025 0.647
C4 Carbon tetramer 4 Πg 323 -152 -475 -2.128
S3 Sulfur trimer 2 A1 281 590 309 0.477
SiH2D2 silane-d2 6 B1 2183 1645 -538 1.327
SiH2D2 silane-d2 8 B2 1601 2276 675 0.703
NH4 Ammonium radical 1 A1 2552 3070 518 0.831
CHFCl Chlorofluoromethyl radical 6 A 540 409 -131 1.321
H2CNCN cyanamide, methylene 3 A' 2208 3131 923 0.705
H2CNCN cyanamide, methylene 4 A' 1621 2373 752 0.683
SNO Nitrogen oxide sulfide 3 A' 792 523 -270 1.516
ONNO NO dimer 3 A1 135 281 147 0.478
ONNO NO dimer 4 torsion A2 117 237 120 0.494
ONNO NO dimer 6 B2 429 667 237 0.644
NSO sulfinyl amidogen 2 A' 1010 772 -238 1.308