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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 MP3=FULL/3-21G*
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 373 173 0.536
HCN+ hydrogen cyanide cation 1 Σ 3050 3783 733 0.806
HCN+ hydrogen cyanide cation 2 Σ 1800 2922 1122 0.616
CH2I2 Diiodomethane 3 A1 704 498 -206 1.413
CH2I2 Diiodomethane 4 A1 285 118 -167 2.416
CH2I2 Diiodomethane 9 B2 738 608 -130 1.213
CH3SCH3+ dimethyl sulfide cation 15 B1 172 140 -32 1.227
C10H8 naphthalene 27 B2g 770 600 -170 1.284
CH3CH2CH2CH3 Butane 5 Ag 1442 435 -1007 3.315
CH3CH2CH2CH3 Butane 7 Ag 1361 843 -518 1.614
CH3CH2CH2CH3 Butane 30 Bu 1461 3065 1604 0.477
CH3CH2CH2CH3 Butane 35 Bu 964 3131 2167 0.308
C3F6 hexafluoropropene 21 A" 60 -11 -71 -5.603
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 1026 -365 1.355
CH2FCH2CH3 1-Fluoropropane 22 A" 890 1325 435 0.672
F2CCCF2 tetrafluoroallene 11 E 90 74 -16 1.218
C3O2 Carbon suboxide 7 Πu 61 30 -31 2.036
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 722 -2357 4.265
C2H4F2 1,2-difluoroethane 18 Bu 295 241 -54 1.223
H2CS- thioformaldehyde anion 4 B1 450 183 -267 2.465
LiOH lithium hydroxide 3 Π 257 479 223 0.535
CFCl2 dichlorofluoromethyl radical 2 A' 747 585 -162 1.278
CH2NH+ Methanimine cation 4 A' 1370 1812 442 0.756
CN Cyano radical 1 Σ 2042 2453 410 0.833
C2H Ethynyl radical 2 Σ 1841 2276 436 0.809
C2H Ethynyl radical 3 torsion Π 372 771 400 0.482
CH3SO2NH2 methanesulfonamide 11 A' 689 549 -140 1.255
CHCl2 dichloromethyl radical 4 A' 190 310 120 0.612
CH2Cl chloromethyl radical 4 B1 402 -124 -526 -3.234
HNC+ hydrogen isocyanide cation 3 Π 578 830 252 0.696
H2O2 Hydrogen peroxide 4 torsion A 371 111 -260 3.344
HN3+ Hydrazoic acid cation 2 A' 1850 3075 1225 0.602
HN3+ Hydrazoic acid cation 4 A' 850 541 -309 1.572
CaBr2 Calcium dibromide 3 Πu 72 128 56 0.563
HOCl+ hypochlorous acid cation 3 A' 830 1329 499 0.625
N2O Nitrous oxide 2 Σ 1285 1053 -232 1.221
N2O Nitrous oxide 3 Π 589 469 -120 1.255
O3 Ozone 3 B2 1042 2238 1196 0.466
OClO- Chlorine dioxide anion 1 A1 790 564 -226 1.401
OClO- Chlorine dioxide anion 2 A1 418 334 -84 1.250
NO Nitric oxide 1 Σ 1876 3664 1788 0.512
NO2+ Nitrogen dioxide cation 3 Πu 639 472 -167 1.353
C3O Tricarbon monoxide 5 Π 109 61 -48 1.784
AsSe Arsenic monoselenide 1 Σ 280 451 171 0.621
NaO2 Sodium superoxide 3 B2 333 567 234 0.587
FO Oxygen monofluoride 1 Σ 1033 2103 1070 0.491
C3 carbon trimer 3 Πu 63 -162 -226 -0.391
C4 Carbon tetramer 4 Πg 323 -228 -551 -1.420
C4 Carbon tetramer 5 Πu 160 114 -46 1.409
S3 Sulfur trimer 2 A1 281 613 332 0.459
NI3 Nitrogen triiodide 3 E 354 620 266 0.571
SiH2D2 silane-d2 6 B1 2183 1689 -494 1.293
SiH2D2 silane-d2 8 B2 1601 2337 736 0.685
H3O+ hydronium cation 2 A1 954 346 -608 2.756
B5H9 pentaborane9 13 B1 240 651 411 0.369
B5H9 pentaborane9 16 B2 1036 807 -229 1.284
B5H9 pentaborane9 18 B2 600 461 -139 1.302
B5H9 pentaborane9 22 E 1409 1143 -266 1.232
CaS Calcium sulfide 1 Σ 459 338 -121 1.357
OPCl Phosphorus oxychloride 2 A' 308 509 201 0.605
OPCl Phosphorus oxychloride 3 A' 492 321 -171 1.534
H2OH2O water dimer 6 A' 311 513 202 0.606
H2OH2O water dimer 7 A' 143 269 126 0.531
H2OH2O water dimer 8 A' 103 215 112 0.479
H2OH2O water dimer 10 A" 523 826 303 0.633
H2OH2O water dimer 11 A" 108 221 113 0.490
H2OH2O water dimer 12 A" 88 140 52 0.629
CHFCl Chlorofluoromethyl radical 6 A 540 390 -150 1.386
NH2NN+ hydrazoic acid, protonated 6 A' 489 308 -181 1.590
H2CNCN cyanamide, methylene 3 A' 2208 3118 910 0.708
H2CNCN cyanamide, methylene 4 A' 1621 2356 735 0.688
H2COO Dioxymethyl radical 6 A' 908 641 -267 1.417
SNO Nitrogen oxide sulfide 3 A' 792 487 -305 1.627
ONNO NO dimer 2 A1 239 343 104 0.697
ONNO NO dimer 3 A1 135 305 171 0.440
ONNO NO dimer 4 torsion A2 117 214 97 0.547
ONNO NO dimer 6 B2 429 682 253 0.629
INO Nitrosyl iodide 2 A' 216 506 290 0.427
INO Nitrosyl iodide 3 A' 470 235 -235 1.998
SSCl2 Thiothionyl chloride 5 A" 377 306 -71 1.230
ClONO chlorine nitrite 4 A' 406 601 195 0.675
ZnCN Zinc monocyanide 3 Π 212 309 97 0.685
SiH5+ Silane, protonated 1 A' 3694 4095 401 0.902
NSO sulfinyl amidogen 2 A' 1010 676 -334 1.494