return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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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 CCSD(T)=FULL/STO-3G
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
H2CO Formaldehyde 5 B2 2843 3287 444 0.865
CH4 Methane 3 T2 3019 3480 461 0.868
C2H6 Ethane 7 Eg 2969 3432 463 0.865
C2H6 Ethane 10 Eu 2985 3444 459 0.867
C2H4 Ethylene 8 B2u 3105 3509 404 0.885
C2H4 Ethylene 10 B3g 3086 3496 410 0.883
C3H6 Cyclopropane 6 A2" 3103 3507 404 0.885
C3H6 Cyclopropane 12 E" 3082 3501 419 0.880
CH2CHCH3 Propene 1 A' 3090 3501 411 0.883
CH2CHCH3 Propene 2 A' 3013 3439 426 0.876
CH2CHCH3 Propene 3 A' 2991 3401 410 0.879
CH2CHCH3 Propene 4 A' 2954 3358 404 0.880
CH2CHCH3 Propene 15 A" 2954 3414 460 0.865
CO2 Carbon dioxide 3 Πu 667 461 -206 1.448
C3H5 Allyl radical 13 B2 3105 3512 407 0.884
SO2 Sulfur dioxide 1 A1 1151 720 -432 1.600
SO2 Sulfur dioxide 2 A1 518 368 -149 1.406
SO2 Sulfur dioxide 3 B2 1362 -961 -2323 -1.417
NH3 Ammonia 2 torsion A1 950 1489 539 0.638
H2O Water 2 A1 1595 2039 444 0.782
NI3 Nitrogen triiodide 1 A1 279 416 137 0.670
NI3 Nitrogen triiodide 3 E 354 562 208 0.630
Na2 Sodium diatomic 1 Σg 158 488 330 0.323