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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-pVQZ
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
H2CO+ formaldehyde cation 1 A1 2580 3151 571 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" 200 311 111 0.644
C2H4+ Ethylene cation 4 torsion Au 84 470 386 0.179
C2H2+ acetylene cation 4 Πg 572 900 328 0.635
CO+ carbon monoxide cation 1 Σ 2184 2620 436 0.834
H2CS- thioformaldehyde anion 4 B1 450 1183 733 0.380
CH2NH+ Methanimine cation 4 A' 1370 1821 451 0.752
CN Cyano radical 1 Σ 2042 2452 410 0.833
C2H Ethynyl radical 3 torsion Π 372 611 240 0.608
H2CC- vinylidene anion 1 A1 2663 3260 597 0.817
H2CC- vinylidene anion 5 B2 2606 3311 705 0.787
CH3 Methyl radical 2 torsion A2" 606 416 -191 1.458
CH2 Methylene 1 A1 2806 3265 459 0.859
CNN Diazocarbene 3 Π 396 321 -75 1.232
HOCO Hydrocarboxyl radical 1 A' 3316 4021 705 0.825
HOCO Hydrocarboxyl radical 1 A' 3636 4139 503 0.878
CH2OH Hydroxymethyl radical 1 A 3650 4179 529 0.873
CH2OH Hydroxymethyl radical 8 torsion A 482 759 277 0.635
CH2OH Hydroxymethyl radical 9 torsion A 234 400 166 0.585
HCO Formyl radical 1 A' 2434 2948 513 0.826
HCCN cyanomethylene 2 Σ 1735 2433 699 0.713
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 4065 629 0.845
OH Hydroxyl radical 1 Σ 3570 4040 470 0.884
OH+ hydoxyl cation 1 Σ 2956 3397 441 0.870
CH2CHO Vinyloxy radical 4 A' 1528 1928 400 0.792
CH2CHO Vinyloxy radical 10 A" 703 1083 380 0.649
CH2Cl chloromethyl radical 4 B1 402 -505 -907 -0.796
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 3319 406 0.878
H2O+ water cation 1 A1 3213 3648 435 0.881
H2O+ water cation 3 B2 3259 3693 434 0.883
O2 Oxygen diatomic 1 Σg 1556 1968 412 0.791
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 773 -259 1.336
NF3 Nitrogen trifluoride 2 A1 647 1239 592 0.522
NF3 Nitrogen trifluoride 3 E 907 595 -312 1.525
NF3 Nitrogen trifluoride 4 E 492 1204 712 0.409
AsSe Arsenic monoselenide 1 Σ 280 446 166 0.628
GaO Gallium monoxide 1 Σ 755 619 -137 1.221
C4 Carbon tetramer 3 Σu 1549 1274 -274 1.215
C4 Carbon tetramer 4 Πg 323 464 141 0.696
N3 azide radical 3 Πu 457 731 274 0.626
HNO Nitrosyl hydride 1 A' 2684 3309 625 0.811
NH4 Ammonium radical 1 A1 2552 3380 828 0.755
BrO+ Bromine monoxide cation 1 Σ 840 599 -241 1.402
NCO isocyanato radical 1 Σ 1921 2361 440 0.814
CHFCl Chlorofluoromethyl radical 6 A 540 437 -103 1.236
SNO Nitrogen oxide sulfide 1 A' 1527 524 -1003 2.912
BrOO Bromine dioxide 1 A' 1487 1203 -284 1.236
BrONO Bromine nitrite 3 A' 587 898 311 0.654
NSO sulfinyl amidogen 3 A' 300 500 200 0.600