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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/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 3504 485 0.862
C2H6 Ethane 5 A2u 2896 3299 403 0.878
C2H6 Ethane 7 Eg 2969 3455 486 0.859
C2H6 Ethane 10 Eu 2985 3467 482 0.861
C2H4 Ethylene 8 B2u 3105 3538 433 0.878
C2H4 Ethylene 10 B3g 3086 3525 439 0.875
C2H5Br Ethyl bromide 1 A' 2988 3460 472 0.864
C2H5Br Ethyl bromide 3 A' 2880 3298 418 0.873
C2H5Br Ethyl bromide 12 A" 3018 3467 449 0.870
C2H5Br Ethyl bromide 13 A" 2988 3423 435 0.873
C3H6 Cyclopropane 6 A2" 3103 3530 427 0.879
C3H6 Cyclopropane 12 E" 3082 3524 442 0.875
CH2CHCHO Acrolein 1 A' 3103 3525 422 0.880
CH2CHCHO Acrolein 2 A' 3028 3436 408 0.881
CH2CHCH3 Propene 1 A' 3090 3529 439 0.876
CH2CHCH3 Propene 2 A' 3013 3461 448 0.871
CH2CHCH3 Propene 3 A' 2991 3427 436 0.873
CH2CHCH3 Propene 4 A' 2954 3383 429 0.873
CH2CHCH3 Propene 5 A' 2871 3287 416 0.874
CH2CHCH3 Propene 15 A" 2954 3437 483 0.860
CO2 Carbon dioxide 1 Σg 1333 1051 -282 1.269
CO2 Carbon dioxide 3 Πu 667 468 -199 1.426
CH2NN diazomethane 6 B1 406 84 -322 4.815
CH2NN diazomethane 7 B2 3150 3576 426 0.881
C2H5F fluoroethane 1 A' 3003 3466 463 0.866
C2H5F fluoroethane 12 A" 3003 3466 463 0.866
NH2CN cyanamide 5 torsion A' 408 887 479 0.460
NH2CN cyanamide 6 A' 487 403 -84 1.209
C6H6 Fulvene 2 A1 3051 3458 407 0.882
C2H3Br vinyl bromide 1 A' 3112 3531 419 0.881
CO Carbon monoxide 1 Σ 2143 1455 -688 1.473
C2F2 difluoroacetylene 4 Πg 270 166 -104 1.622
CaO Calcium monoxide 1 Σ 723 450 -273 1.607
H2 Hydrogen diatomic 1 Σg 4161 5044 883 0.825
C3H5 Allyl radical 1 A1 3114 3545 431 0.878
C3H5 Allyl radical 13 B2 3105 3545 440 0.876
SO2 Sulfur dioxide 2 A1 518 422 -96 1.228
NaBr Sodium Bromide 1 Σ 299 477 178 0.627
NH3 Ammonia 2 torsion A1 950 1485 535 0.640
H2O Water 2 A1 1595 2047 452 0.779
BN boron nitride 1 Σ 1490 2226 736 0.669
Li2O dilithium oxide 3 Πu 112 61 -51 1.842
CaOH Calcium monohydroxide 3 Π 353 -416 -769 -0.848
NI3 Nitrogen triiodide 1 A1 279 421 142 0.663
NI3 Nitrogen triiodide 3 E 354 577 223 0.614
CSe Carbon monoselenide 1 Σ 1026 531 -494 1.930