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 MP4=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 3505 486 0.861
C2H6 Ethane 5 A2u 2896 3300 404 0.878
C2H6 Ethane 7 Eg 2969 3456 487 0.859
C2H6 Ethane 10 Eu 2985 3468 483 0.861
C2H4 Ethylene 8 B2u 3105 3539 434 0.877
C2H4 Ethylene 10 B3g 3086 3526 440 0.875
C3H6 Cyclopropane 6 A2" 3103 3531 428 0.879
C3H6 Cyclopropane 12 E" 3082 3525 443 0.874
CH2CHCH3 Propene 1 A' 3090 3529 439 0.876
CH2CHCH3 Propene 2 A' 3013 3461 448 0.870
CH2CHCH3 Propene 3 A' 2991 3428 437 0.873
CH2CHCH3 Propene 4 A' 2954 3384 430 0.873
CH2CHCH3 Propene 5 A' 2871 3287 416 0.873
CH2CHCH3 Propene 15 A" 2954 3438 484 0.859
CO2 Carbon dioxide 1 Σg 1333 1051 -282 1.268
CO2 Carbon dioxide 3 Πu 667 468 -199 1.425
CO Carbon monoxide 1 Σ 2143 1457 -686 1.471
H2 Hydrogen diatomic 1 Σg 4161 5044 883 0.825
C3H5 Allyl radical 1 A1 3114 3546 432 0.878
C3H5 Allyl radical 13 B2 3105 3545 440 0.876
SO2 Sulfur dioxide 2 A1 518 422 -96 1.228
NH3 Ammonia 2 torsion A1 950 1485 535 0.640
H2O Water 2 A1 1595 2047 452 0.779
NI3 Nitrogen triiodide 1 A1 279 421 142 0.663
NI3 Nitrogen triiodide 3 E 354 577 223 0.614