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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-pVDZ
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
H2CO+ formaldehyde cation 1 A1 2580 3166 586 0.815
H2CO+ formaldehyde cation 5 B2 2718 3316 598 0.820
C2H4+ Ethylene cation 4 torsion Au 84 465 381 0.181
C2H2+ acetylene cation 4 Πg 572 825 253 0.694
CO+ carbon monoxide cation 1 Σ 2184 2599 415 0.840
H2CS- thioformaldehyde anion 4 B1 450 1326 876 0.339
CH2NH+ Methanimine cation 4 A' 1370 1820 450 0.753
CN Cyano radical 1 Σ 2042 2445 402 0.835
H2CC- vinylidene anion 1 A1 2663 3266 603 0.815
H2CC- vinylidene anion 5 B2 2606 3266 660 0.798
CH3 Methyl radical 2 torsion A2" 606 420 -186 1.443
CH2 Methylene 1 A1 2806 3267 461 0.859
CNN Diazocarbene 3 Π 396 292 -104 1.356
HOCO Hydrocarboxyl radical 1 A' 3316 4025 709 0.824
HOCO Hydrocarboxyl radical 1 A' 3636 4141 505 0.878
CH2OH Hydroxymethyl radical 1 A 3650 4180 530 0.873
CH2OH Hydroxymethyl radical 8 torsion A 482 760 278 0.634
CH2OH Hydroxymethyl radical 9 torsion A 234 400 166 0.585
HCO Formyl radical 1 A' 2434 2972 538 0.819
ClCO carbonyl monochloride 3 A' 335 147 -187 2.270
HCCN cyanomethylene 2 Σ 1735 2439 704 0.711
HCCN cyanomethylene 5 Π 129 -978 -1107 -0.132
C2H3 vinyl 2 A' 2953 3358 405 0.879
C2H3+ vinyl cation 2 A1 2217 3201 984 0.693
HO2 Hydroperoxy radical 1 A' 3436 4071 635 0.844
OH Hydroxyl radical 1 Σ 3570 4036 467 0.884
OH+ hydoxyl cation 1 Σ 2956 3395 439 0.871
CHCl2 dichloromethyl radical 4 A' 190 318 128 0.597
CH2CHO Vinyloxy radical 10 A" 703 1071 368 0.657
CH2CH2OH 2-hydroxy ethyl radical 1 A' 3626 4168 542 0.870
CH2Cl chloromethyl radical 4 B1 402 -526 -928 -0.765
HCP+ Phosphaethyne cation 1 Σ 2986 3424 438 0.872
HNC+ hydrogen isocyanide cation 1 Σ 3365 3769 404 0.893
H2O+ water cation 1 A1 3213 3644 431 0.882
H2O+ water cation 3 B2 3259 3703 444 0.880
O2 Oxygen diatomic 1 Σg 1556 1978 422 0.787
O2+ diatomic oxygen cation 1 Σg 1873 2509 636 0.746
HN3+ Hydrazoic acid cation 2 A' 1850 2723 873 0.679
NF3 Nitrogen trifluoride 1 A1 1032 760 -272 1.357
NF3 Nitrogen trifluoride 2 A1 647 1220 573 0.530
NF3 Nitrogen trifluoride 3 E 907 584 -323 1.553
NF3 Nitrogen trifluoride 4 E 492 1190 698 0.413
AsSe Arsenic monoselenide 1 Σ 280 443 163 0.632
GaO Gallium monoxide 1 Σ 755 594 -161 1.270
C4 Carbon tetramer 3 Σu 1549 1265 -284 1.224
N3 azide radical 3 Πu 457 706 249 0.647
HNO Nitrosyl hydride 1 A' 2684 3322 638 0.808
NH4 Ammonium radical 1 A1 2552 3367 815 0.758
BrO+ Bromine monoxide cation 1 Σ 840 526 -314 1.598
SCN thiocyanato radical 1 Σ 1942 2446 503 0.794
NCO isocyanato radical 1 Σ 1921 2353 431 0.817
CHFCl Chlorofluoromethyl radical 6 A 540 430 -110 1.255
SNO Nitrogen oxide sulfide 1 A' 1527 512 -1015 2.981
BrOO Bromine dioxide 1 A' 1487 1190 -297 1.249
BrONO Bromine nitrite 3 A' 587 898 311 0.654
HSO3 Hydroxysulfonyl radical 1 A 3540 4048 508 0.874
HSO3 Hydroxysulfonyl radical 4 A 1097 898 -199 1.222
NSO sulfinyl amidogen 3 A' 300 472 172 0.636