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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 ROHF/aug-cc-pVTZ
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
H2CO+ formaldehyde cation 1 A1 2580 3152 572 0.819
H2CO+ formaldehyde cation 5 B2 2718 3291 573 0.826
C2H4+ Ethylene cation 4 torsion Au 84 448 364 0.188
C2H2+ acetylene cation 4 Πg 572 895 323 0.639
CO+ carbon monoxide cation 1 Σ 2184 2614 430 0.836
H2CS- thioformaldehyde anion 4 B1 450 1158 708 0.389
CH2NH+ Methanimine cation 4 A' 1370 1819 449 0.753
CN Cyano radical 1 Σ 2042 2449 406 0.834
C2H Ethynyl radical 3 torsion Π 372 611 240 0.608
H2CC- vinylidene anion 1 A1 2663 3262 599 0.816
H2CC- vinylidene anion 5 B2 2606 3298 692 0.790
CH3 Methyl radical 2 torsion A2" 606 414 -192 1.464
CH2 Methylene 1 A1 2806 3264 459 0.860
CNN Diazocarbene 3 Π 396 323 -73 1.227
HOCO Hydrocarboxyl radical 1 A' 3316 4015 699 0.826
HOCO Hydrocarboxyl radical 1 A' 3636 4132 497 0.880
CH2OH Hydroxymethyl radical 1 A 3650 4171 521 0.875
CH2OH Hydroxymethyl radical 8 torsion A 482 762 280 0.633
CH2OH Hydroxymethyl radical 9 torsion A 234 397 163 0.589
HCO Formyl radical 1 A' 2434 2953 518 0.824
ClCO carbonyl monochloride 3 A' 335 237 -97 1.410
HCCN cyanomethylene 2 Σ 1735 2433 698 0.713
HCCN cyanomethylene 5 Π 129 -959 -1088 -0.134
C2H3+ vinyl cation 2 A1 2217 3185 968 0.696
HO2 Hydroperoxy radical 1 A' 3436 4059 622 0.847
OH Hydroxyl radical 1 Σ 3570 4032 462 0.885
OH+ hydoxyl cation 1 Σ 2956 3390 433 0.872
CHCl2 dichloromethyl radical 4 A' 190 319 129 0.597
CH2CHO Vinyloxy radical 10 A" 703 1083 380 0.649
CH2CH2OH 2-hydroxy ethyl radical 1 A' 3626 4157 531 0.872
CH2Cl chloromethyl radical 4 B1 402 -516 -918 -0.779
HCP+ Phosphaethyne cation 1 Σ 2986 3423 437 0.872
HNC+ hydrogen isocyanide cation 1 Σ 3365 3777 412 0.891
HF+ hydrogen fluoride cation 1 Σ 2913 3320 408 0.877
H2O+ water cation 1 A1 3213 3641 428 0.883
H2O+ water cation 3 B2 3259 3686 427 0.884
O2 Oxygen diatomic 1 Σg 1556 1960 404 0.794
O2+ diatomic oxygen cation 1 Σg 1873 2487 614 0.753
HN3+ Hydrazoic acid cation 2 A' 1850 2713 863 0.682
NF3 Nitrogen trifluoride 1 A1 1032 771 -261 1.339
NF3 Nitrogen trifluoride 2 A1 647 1236 589 0.523
NF3 Nitrogen trifluoride 3 E 907 593 -314 1.530
NF3 Nitrogen trifluoride 4 E 492 1201 709 0.410
AsSe Arsenic monoselenide 1 Σ 280 445 165 0.629
GaO Gallium monoxide 1 Σ 755 613 -142 1.231
C4 Carbon tetramer 3 Σu 1549 1276 -273 1.214
C4 Carbon tetramer 4 Πg 323 464 141 0.696
N3 azide radical 3 Πu 457 731 274 0.625
HNO Nitrosyl hydride 1 A' 2684 3311 627 0.811
NH4 Ammonium radical 1 A1 2552 3378 826 0.756
BrO+ Bromine monoxide cation 1 Σ 840 596 -244 1.409
SCN thiocyanato radical 1 Σ 1942 2445 502 0.795
NCO isocyanato radical 1 Σ 1921 2360 439 0.814
CHFCl Chlorofluoromethyl radical 6 A 540 435 -105 1.243
SNO Nitrogen oxide sulfide 1 A' 1527 522 -1005 2.925
BrOO Bromine dioxide 1 A' 1487 1195 -292 1.244
BrONO Bromine nitrite 3 A' 587 892 305 0.658
NSO sulfinyl amidogen 3 A' 300 494 194 0.607