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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/cc-pVQZ
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
H2CO+ formaldehyde cation 1 A1 2580 3150 570 0.819
H2CO+ formaldehyde cation 5 B2 2718 3291 573 0.826
CH3OH Methyl alcohol 1 A' 3681 4178 497 0.881
CH3OH Methyl alcohol 12 torsion A" 200 313 113 0.638
C2H4+ Ethylene cation 4 torsion Au 84 476 392 0.177
C2H2+ acetylene cation 4 Πg 572 900 328 0.635
CO+ carbon monoxide cation 1 Σ 2184 2620 436 0.833
H2CS- thioformaldehyde anion 4 B1 450 -176 -626 -2.558
CH2NH+ Methanimine cation 4 A' 1370 1821 451 0.752
CN Cyano radical 1 Σ 2042 2453 411 0.832
C2H Ethynyl radical 3 torsion Π 372 611 240 0.608
H2CC- vinylidene anion 5 B2 2606 3036 430 0.858
CH3 Methyl radical 2 torsion A2" 606 411 -195 1.475
CH2 Methylene 1 A1 2806 3265 459 0.859
CNN Diazocarbene 3 Π 396 323 -73 1.227
HOCO Hydrocarboxyl radical 1 A' 3316 4022 706 0.824
HOCO Hydrocarboxyl radical 1 A' 3636 4141 505 0.878
CH2OH Hydroxymethyl radical 1 A 3650 4178 528 0.874
CH2OH Hydroxymethyl radical 8 torsion A 482 764 282 0.631
CH2OH Hydroxymethyl radical 9 torsion A 234 398 164 0.588
HCO Formyl radical 1 A' 2434 2943 509 0.827
ClCO carbonyl monochloride 3 A' 335 272 -62 1.229
HCCN cyanomethylene 2 Σ 1735 2435 700 0.712
HCCN cyanomethylene 5 Π 129 -958 -1087 -0.135
C2H3+ vinyl cation 2 A1 2217 3184 967 0.696
HO2 Hydroperoxy radical 1 A' 3436 4067 631 0.845
OH Hydroxyl radical 1 Σ 3570 4042 472 0.883
OH+ hydoxyl cation 1 Σ 2956 3398 442 0.870
CH2CHO Vinyloxy radical 4 A' 1528 1932 404 0.791
CH2CHO Vinyloxy radical 10 A" 703 1083 380 0.649
CH2Cl chloromethyl radical 4 B1 402 -505 -907 -0.797
HCP+ Phosphaethyne cation 1 Σ 2986 3425 439 0.872
HNC+ hydrogen isocyanide cation 1 Σ 3365 3780 415 0.890
HF+ hydrogen fluoride cation 1 Σ 2913 3322 409 0.877
H2O+ water cation 1 A1 3213 3649 436 0.880
H2O+ water cation 3 B2 3259 3694 435 0.882
O2 Oxygen diatomic 1 Σg 1556 1970 414 0.790
O2+ diatomic oxygen cation 1 Σg 1873 2493 620 0.751
HN3+ Hydrazoic acid cation 2 A' 1850 2714 864 0.682
NF3 Nitrogen trifluoride 1 A1 1032 772 -260 1.337
NF3 Nitrogen trifluoride 2 A1 647 1240 593 0.522
NF3 Nitrogen trifluoride 3 E 907 594 -313 1.527
NF3 Nitrogen trifluoride 4 E 492 1205 713 0.408
AsSe Arsenic monoselenide 1 Σ 280 446 166 0.628
GaO Gallium monoxide 1 Σ 755 623 -132 1.213
C4 Carbon tetramer 3 Σu 1549 1279 -269 1.211
C4 Carbon tetramer 4 Πg 323 466 143 0.693
N3 azide radical 3 Πu 457 732 275 0.624
HNO Nitrosyl hydride 1 A' 2684 3306 622 0.812
NH4 Ammonium radical 1 A1 2552 3265 713 0.782
BrO+ Bromine monoxide cation 1 Σ 840 600 -240 1.401
NCO isocyanato radical 1 Σ 1921 2363 442 0.813
CHFCl Chlorofluoromethyl radical 6 A 540 436 -104 1.238
SNO Nitrogen oxide sulfide 1 A' 1527 524 -1004 2.917
BrOO Bromine dioxide 1 A' 1487 1202 -285 1.237
BrONO Bromine nitrite 3 A' 587 898 311 0.654
NSO sulfinyl amidogen 3 A' 300 501 201 0.599