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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 ROMP2/6-31G
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
H2CO+ formaldehyde cation 1 A1 2580 2996 416 0.861
H2CO+ formaldehyde cation 5 B2 2718 3144 426 0.864
C2H4+ Ethylene cation 4 torsion Au 84 -237 -321 -0.355
CH3SCH3+ dimethyl sulfide cation 15 B1 172 106 -66 1.627
H2CS- thioformaldehyde anion 4 B1 450 112 -338 4.025
SiF2+ Silicon difluoride cation 2 A1 350 263 -87 1.329
CFCl2 dichlorofluoromethyl radical 2 A' 747 565 -182 1.321
CN Cyano radical 1 Σ 2042 1562 -480 1.307
CH3 Methyl radical 2 torsion A2" 606 457 -150 1.328
CNN Diazocarbene 3 Π 396 277 -119 1.430
CH2OH Hydroxymethyl radical 8 torsion A 482 727 245 0.663
CH2OH Hydroxymethyl radical 9 torsion A 234 444 210 0.527
HCO Formyl radical 1 A' 2434 2837 402 0.858
ClCO carbonyl monochloride 2 A' 570 922 352 0.619
C2H3+ vinyl cation 2 A1 2217 3049 832 0.727
HO2 Hydroperoxy radical 3 A' 1098 896 -201 1.224
CHCl2 dichloromethyl radical 4 A' 190 285 95 0.667
CBr Carbon monobromide 1 Σ 720 587 -133 1.226
CH2Cl chloromethyl radical 4 B1 402 -290 -692 -1.388
SO2 Sulfur dioxide 2 A1 518 401 -117 1.293
O2 Oxygen diatomic 1 Σg 1556 621 -936 2.507
HN3 hydrogen azide 4 A' 1151 943 -207 1.220
HN3 hydrogen azide 6 A" 607 459 -148 1.322
HN3+ Hydrazoic acid cation 4 A' 850 659 -191 1.290
NF3 Nitrogen trifluoride 1 A1 1032 542 -490 1.902
NF3 Nitrogen trifluoride 3 E 907 398 -509 2.279
NF3 Nitrogen trifluoride 4 E 492 799 307 0.615
HeH+ Helium hydride cation 1 Σ 2911 2141 -770 1.359
OClO- Chlorine dioxide anion 1 A1 790 585 -205 1.351
OClO- Chlorine dioxide anion 2 A1 418 267 -151 1.566
OClO Chlorine dioxide 2 A1 448 345 -103 1.299
OClO Chlorine dioxide 3 B2 1110 598 -513 1.858
NO2+ Nitrogen dioxide cation 3 Πu 639 391 -248 1.635
SF5 Sulfur pentafluoride 2 A1 633 309 -324 2.048
SF5 Sulfur pentafluoride 7 E 818 514 -304 1.592
SF5 Sulfur pentafluoride 8 E 525 312 -213 1.684
SF5 Sulfur pentafluoride 9 E 387 197 -190 1.961
NaO2 Sodium superoxide 1 A1 1094 707 -387 1.547
LiO2 Lithium dioxide 1 A1 1094 763 -331 1.434
C4 Carbon tetramer 3 Σu 1549 2388 839 0.649
C4 Carbon tetramer 4 Πg 323 -450 -773 -0.717
C4 Carbon tetramer 5 Πu 160 86 -74 1.860
NCl nitrogen monochloride 1 Σ 817 663 -155 1.233
S3- Sulfur trimer anion 3 B2 594 -1008 -1602 -0.590
SeO Selenium monoxide 1 Σ 906 1501 596 0.603
Be(OH)2 Beryllium hydroxide 8 B 456 378 -78 1.206
SO Sulfur monoxide 1 Σ 1138 1711 573 0.665
SO Sulfur monoxide 1 Σ 1054 639 -416 1.651
PF2 Phosphorus difluoride 2 A1 366 288 -78 1.269
SiCl Clorosilylidyne 1 Σ 531 435 -96 1.220
NBr nitrogen monobromide 1 Σ 682 558 -125 1.224
HNO Nitrosyl hydride 3 A' 1501 1208 -293 1.243
PO Phosphorus monoxide 1 Σ 1220 974 -247 1.253
HS2 Thiosulfeno radical 3 A' 596 446 -150 1.337
ClO Monochlorine monoxide 1 Σ 843 674 -169 1.250
SCl sulfur monochloride 1 Σ 577 447 -130 1.290
BrO Bromine monoxide 1 Σ 716 576 -140 1.243
BrO+ Bromine monoxide cation 1 Σ 840 1200 360 0.700
SCN thiocyanato radical 2 Σ 762 612 -150 1.246
SCN thiocyanato radical 3 Π 376 301 -75 1.250
AsCl Arsenic monochloride 1 Σ 439 341 -98 1.288
AlP Aluminum monophosphide 1 Σ 457 333 -124 1.372
OBrO Bromine dioxide radical 3 B2 849 561 -288 1.513
NCO isocyanato radical 1 Σ 1921 1467 -454 1.310
NCO isocyanato radical 3 Π 535 424 -111 1.262
S2 Sulfur diatomic 1 Σg 720 469 -251 1.534
CHFCl Chlorofluoromethyl radical 6 A 540 369 -171 1.465
ZnCH3 Zinc monomethyl 6 E 315 654 339 0.482
ClSO Sulfur chloride oxide 1 A' 1163 664 -499 1.752
ClONO chlorine nitrite 2 A' 858 707 -151 1.213
ClONO chlorine nitrite 4 A' 406 333 -73 1.218
ClONO chlorine nitrite 5 A' 270 185 -85 1.462
BrOO Bromine dioxide 1 A' 1487 797 -690 1.866
ZnCN Zinc monocyanide 3 Π 212 142 -70 1.494
HSO3 Hydroxysulfonyl radical 3 A 1296 1065 -231 1.217
HSO3 Hydroxysulfonyl radical 4 A 1097 838 -259 1.309
HSO3 Hydroxysulfonyl radical 5 A 759 600 -160 1.267
HSO3 Hydroxysulfonyl radical 6 A 538 417 -121 1.291
NSO sulfinyl amidogen 1 A' 1202 1683 481 0.714
NSO sulfinyl amidogen 2 A' 1010 727 -283 1.389