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
MP4/6-31G
Calculated values were scaled by 0.9438.
Species | Name | mode | int rot | Symmetry | Experiment | Theory | difference | ratio |
---|---|---|---|---|---|---|---|---|
C2H2 | Acetylene | 4 | Πg | 612 | 332 | -280 | 1.843 | |
HNCO | Isocyanic acid | 6 | A" | 656 | 494 | -162 | 1.329 | |
CO2 | Carbon dioxide | 1 | Σg | 1333 | 1046 | -287 | 1.274 | |
CO2 | Carbon dioxide | 3 | Πu | 667 | 473 | -194 | 1.411 | |
CO | Carbon monoxide | 1 | Σ | 2143 | 1583 | -560 | 1.354 | |
C4H6O | Cyclobutanone | 13 | A2 | 909 | 685 | -224 | 1.326 | |
CS | carbon monosulfide | 1 | Σ | 1272 | 806 | -466 | 1.578 | |
SO2 | Sulfur dioxide | 1 | A1 | 1151 | 863 | -288 | 1.334 | |
SO2 | Sulfur dioxide | 2 | A1 | 518 | 364 | -153 | 1.421 | |
NH3 | Ammonia | 2 | torsion | A1 | 950 | 729 | -221 | 1.303 |
O2 | Oxygen diatomic | 1 | Σg | 1556 | 991 | -566 | 1.571 | |
Cl2 | Chlorine diatomic | 1 | Σg | 554 | 382 | -172 | 1.450 | |
NO | Nitric oxide | 1 | Σ | 1876 | 3559 | 1683 | 0.527 | |
Si2 | Silicon diatomic | 1 | Σg | 507 | 390 | -117 | 1.299 |