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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/6-31G(2df,p)
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 328 128 0.610
HCN+ hydrogen cyanide cation 1 Σ 3050 3568 518 0.855
HCN+ hydrogen cyanide cation 2 Σ 1800 2763 963 0.651
CH3CH2CH2CH3 Butane 5 Ag 1442 434 -1008 3.323
CH3CH2CH2CH3 Butane 8 Ag 1151 875 -276 1.316
CH3CH2CH2CH3 Butane 30 Bu 1461 3118 1657 0.469
CH3CH2CH2CH3 Butane 35 Bu 964 3201 2237 0.301
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 1084 -307 1.283
CH2FCH2CH3 1-Fluoropropane 22 A" 890 1319 429 0.675
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 723 -2356 4.258
CO+ carbon monoxide cation 1 Σ 2184 2719 536 0.803
C6H6 Benzvalene 10 A1 996 796 -200 1.252
H2CS- thioformaldehyde anion 4 B1 450 -97 -547 -4.616
LiOH lithium hydroxide 1 Σ 3688 4139 452 0.891
CH2NH+ Methanimine cation 4 A' 1370 1878 508 0.730
CN Cyano radical 1 Σ 2042 2720 678 0.751
C2H Ethynyl radical 2 Σ 1841 2455 614 0.750
C2H Ethynyl radical 3 torsion Π 372 846 474 0.439
HOCO Hydrocarboxyl radical 1 A' 3316 3787 471 0.876
HNCS Isothiocyanic acid 5 A' 469 378 -92 1.243
CH3SO2NH2 methanesulfonamide 15 A" 3320 3741 421 0.888
CHCl2 dichloromethyl radical 4 A' 190 311 121 0.611
CH2Cl chloromethyl radical 4 B1 402 -204 -606 -1.968
HNC+ hydrogen isocyanide cation 2 Σ 2195 2719 524 0.807
HN3+ Hydrazoic acid cation 2 A' 1850 2900 1050 0.638
HeH+ Helium hydride cation 1 Σ 2911 3316 405 0.878
O3 Ozone 3 B2 1042 1758 716 0.593
NO Nitric oxide 1 Σ 1876 2674 798 0.701
AsSe Arsenic monoselenide 1 Σ 280 521 241 0.538
NS Mononitrogen monosulfide 1 Σ 1204 1668 464 0.722
GaP Gallium monophosphide 1 Σ 284 408 124 0.696
C3 carbon trimer 3 Πu 63 178 114 0.357
N3 azide radical 3 Πu 457 655 198 0.697
S3 Sulfur trimer 2 A1 281 624 343 0.450
SiH2D2 silane-d2 6 B1 2183 1682 -501 1.298
SiH2D2 silane-d2 8 B2 1601 2327 726 0.688
B5H9 pentaborane9 13 B1 240 612 372 0.392
B5H9 pentaborane9 16 B2 1036 835 -201 1.241
B5H9 pentaborane9 22 E 1409 1124 -285 1.253
OPCl Phosphorus oxychloride 2 A' 308 527 219 0.584
OPCl Phosphorus oxychloride 3 A' 492 321 -171 1.532
H2OH2O water dimer 8 A' 103 151 48 0.684
CHFCl Chlorofluoromethyl radical 6 A 540 418 -122 1.290
H2CNCN cyanamide, methylene 3 A' 2208 3170 962 0.697
H2CNCN cyanamide, methylene 4 A' 1621 2432 811 0.667
SNO Nitrogen oxide sulfide 1 A' 1527 1957 429 0.781
SNO Nitrogen oxide sulfide 3 A' 792 519 -273 1.525
ONNO NO dimer 2 A1 239 347 108 0.689
ONNO NO dimer 3 A1 135 306 171 0.440
ONNO NO dimer 4 torsion A2 117 256 139 0.457
ONNO NO dimer 6 B2 429 694 265 0.618
ClONO chlorine nitrite 4 A' 406 650 244 0.625