Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology | |
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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
QCISD(TQ)/STO-3G
Calculated values were scaled by 1.
Species | Name | mode | int rot | Symmetry | Experiment | Theory | difference | ratio |
---|---|---|---|---|---|---|---|---|
H2CO | Formaldehyde | 5 | B2 | 2843 | 3294 | 451 | 0.863 | |
CH4 | Methane | 3 | T2 | 3019 | 3478 | 459 | 0.868 | |
C2H6 | Ethane | 7 | Eg | 2969 | 3430 | 461 | 0.866 | |
C2H6 | Ethane | 10 | Eu | 2985 | 3442 | 457 | 0.867 | |
C2H4 | Ethylene | 8 | B2u | 3105 | 3507 | 402 | 0.885 | |
C2H4 | Ethylene | 10 | B3g | 3086 | 3494 | 408 | 0.883 | |
C3H6 | Cyclopropane | 6 | A2" | 3103 | 3504 | 401 | 0.885 | |
C3H6 | Cyclopropane | 12 | E" | 3082 | 3498 | 416 | 0.881 | |
CH2CHCH3 | Propene | 1 | A' | 3090 | 3499 | 409 | 0.883 | |
CH2CHCH3 | Propene | 2 | A' | 3013 | 3436 | 423 | 0.877 | |
CH2CHCH3 | Propene | 3 | A' | 2991 | 3399 | 408 | 0.880 | |
CH2CHCH3 | Propene | 4 | A' | 2954 | 3355 | 401 | 0.880 | |
CH2CHCH3 | Propene | 15 | A" | 2954 | 3411 | 457 | 0.866 | |
CO2 | Carbon dioxide | 3 | Πu | 667 | 453 | -214 | 1.473 | |
C3H5 | Allyl radical | 13 | B2 | 3105 | 3510 | 405 | 0.885 | |
SO2 | Sulfur dioxide | 1 | A1 | 1151 | 823 | -328 | 1.399 | |
SO2 | Sulfur dioxide | 2 | A1 | 518 | 375 | -143 | 1.381 | |
SO2 | Sulfur dioxide | 3 | B2 | 1362 | 247 | -1114 | 5.506 | |
NH3 | Ammonia | 2 | torsion | A1 | 950 | 1488 | 538 | 0.638 |
H2O | Water | 2 | A1 | 1595 | 2038 | 443 | 0.783 | |
Na2 | Sodium diatomic | 1 | Σg | 158 | 483 | 326 | 0.326 |