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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 MP4=FULL/6-311+G(3df,2p)
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 288 88 0.694
HCN+ hydrogen cyanide cation 1 Σ 3050 3573 523 0.854
HCN+ hydrogen cyanide cation 2 Σ 1800 2774 974 0.649
CH3SCH3+ dimethyl sulfide cation 15 B1 172 118 -54 1.457
CH3CH2CH2CH3 Butane 5 Ag 1442 428 -1014 3.373
CH3CH2CH2CH3 Butane 8 Ag 1151 854 -297 1.348
CH3CH2CH2CH3 Butane 36 Bu 271 3120 2849 0.087
C5H8 Bicyclo[1.1.1]pentane 3 A1' 1509 3050 1541 0.495
C5H8 Bicyclo[1.1.1]pentane 4 A1' 1107 1552 445 0.713
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 1043 -348 1.333
CH2FCH2CH3 1-Fluoropropane 22 A" 890 1279 389 0.696
CO+ carbon monoxide cation 1 Σ 2184 2737 553 0.798
H2CS- thioformaldehyde anion 4 B1 450 317 -133 1.420
CaO Calcium monoxide 1 Σ 723 1536 813 0.470
LiOH lithium hydroxide 3 Π 257 425 169 0.603
CH2NH+ Methanimine cation 4 A' 1370 1861 491 0.736
CN Cyano radical 1 Σ 2042 2720 678 0.751
CH2Cl chloromethyl radical 4 B1 402 127 -275 3.173
HNC+ hydrogen isocyanide cation 2 Σ 2195 2693 497 0.815
HN3+ Hydrazoic acid cation 2 A' 1850 2977 1127 0.621
CaBr2 Calcium dibromide 3 Πu 72 39 -33 1.824
NO Nitric oxide 1 Σ 1876 3293 1417 0.570
NaO2 Sodium superoxide 3 B2 333 602 269 0.553
C3 carbon trimer 3 Πu 63 184 121 0.344
S3 Sulfur trimer 2 A1 281 574 293 0.490
SiH2D2 silane-d2 6 B1 2183 1640 -543 1.331
SiH2D2 silane-d2 8 B2 1601 2268 667 0.706
NH4 Ammonium radical 1 A1 2552 3085 533 0.827
GeO Germanium monoxide 1 Σ 977 749 -228 1.304
OPCl Phosphorus oxychloride 2 A' 308 497 189 0.620
OPCl Phosphorus oxychloride 3 A' 492 298 -194 1.650
CHFCl Chlorofluoromethyl radical 6 A 540 414 -126 1.304
H2CNCN cyanamide, methylene 3 A' 2208 3094 886 0.714
H2CNCN cyanamide, methylene 4 A' 1621 2148 527 0.755
SNO Nitrogen oxide sulfide 1 A' 1527 15649 14122 0.098
SNO Nitrogen oxide sulfide 3 A' 792 -7162 -7954 -0.111