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 CISD/STO-3G
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
H2CO Formaldehyde 1 A1 2782 3249 467 0.856
H2CO Formaldehyde 5 B2 2843 3373 530 0.843
CH4 Methane 3 T2 3019 3507 488 0.861
C2H6 Ethane 5 A2u 2896 3331 435 0.870
C2H6 Ethane 7 Eg 2969 3488 519 0.851
C2H6 Ethane 10 Eu 2985 3500 515 0.853
C2H4 Ethylene 1 Ag 3026 3445 419 0.878
C2H4 Ethylene 5 B1u 2989 3413 425 0.876
C2H4 Ethylene 8 B2u 3105 3576 471 0.868
C2H4 Ethylene 10 B3g 3086 3563 477 0.866
C3H6 Cyclopropane 1 A1' 3038 3453 415 0.880
C3H6 Cyclopropane 6 A2" 3103 3583 480 0.866
C3H6 Cyclopropane 8 E' 3025 3430 405 0.882
C3H6 Cyclopropane 12 E" 3082 3577 495 0.862
CH2CHCH3 Propene 1 A' 3090 3587 497 0.862
CH2CHCH3 Propene 2 A' 3013 3524 511 0.855
CH2CHCH3 Propene 3 A' 2991 3489 498 0.857
CH2CHCH3 Propene 4 A' 2954 3442 488 0.858
CH2CHCH3 Propene 5 A' 2871 3351 480 0.857
CH2CHCH3 Propene 15 A" 2954 3500 546 0.844
CO2 Carbon dioxide 3 Πu 667 484 -183 1.379
H2 Hydrogen diatomic 1 Σg 4161 5002 841 0.832
C3H5 Allyl radical 1 A1 3114 3592 478 0.867
C3H5 Allyl radical 2 A1 3048 3488 440 0.874
C3H5 Allyl radical 13 B2 3105 3591 486 0.865
C3H5 Allyl radical 14 B2 3016 3430 414 0.879
NH3 Ammonia 2 torsion A1 950 1490 540 0.638
SOCl2 thionyl chloride 4 A' 194 146 -48 1.327
SOCl2 thionyl chloride 6 A" 284 229 -55 1.238
H2O Water 2 A1 1595 2049 454 0.778
HN3 hydrogen azide 5 A' 534 407 -127 1.311
HN3 hydrogen azide 6 A" 607 443 -164 1.369
Li2O dilithium oxide 3 Πu 112 188 77 0.593
NI3 Nitrogen triiodide 1 A1 279 435 156 0.641
NI3 Nitrogen triiodide 3 E 354 623 269 0.568
Na2 Sodium diatomic 1 Σg 158 483 326 0.326