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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/6-311G**
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 342 142 0.585
HCN+ hydrogen cyanide cation 1 Σ 3050 3653 603 0.835
HCN+ hydrogen cyanide cation 2 Σ 1800 2828 1028 0.637
CH2I2 Diiodomethane 3 A1 704 496 -208 1.418
CH2I2 Diiodomethane 4 A1 285 122 -163 2.329
CH2I2 Diiodomethane 7 B1 896 740 -156 1.210
CH2I2 Diiodomethane 9 B2 738 608 -130 1.214
CH3SCH3+ dimethyl sulfide cation 15 B1 172 138 -34 1.242
C10H8 naphthalene 12 Au 581 464 -117 1.251
C10H8 naphthalene 27 B2g 770 440 -330 1.750
C10H8 naphthalene 28 B2g 461 -308 -769 -1.494
C6H4Cl2 1,4-dichlorobenzene 16 B2g 687 486 -201 1.415
CH3CH2CH2CH3 Butane 5 Ag 1442 431 -1011 3.347
CH3CH2CH2CH3 Butane 8 Ag 1151 866 -285 1.329
CH3CH2CH2CH3 Butane 36 Bu 271 3159 2888 0.086
CHSNH2 thioformamide 12 A" 393 111 -282 3.541
C3F6 hexafluoropropene 21 A" 60 39 -21 1.546
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 1077 -314 1.291
CH2FCH2CH3 1-Fluoropropane 22 A" 890 1307 417 0.681
C3O2 Carbon suboxide 7 Πu 61 -54 -115 -1.129
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 701 -2378 4.391
CO+ carbon monoxide cation 1 Σ 2184 2725 541 0.801
C6H6 Benzvalene 10 A1 996 782 -214 1.274
H2CS- thioformaldehyde anion 4 B1 450 92 -358 4.869
LiOH lithium hydroxide 1 Σ 3688 4145 457 0.890
LiOH lithium hydroxide 3 Π 257 397 140 0.647
CH2NH+ Methanimine cation 4 A' 1370 1862 492 0.736
CN Cyano radical 1 Σ 2042 2671 629 0.765
C2H Ethynyl radical 2 Σ 1841 2390 549 0.770
C2H Ethynyl radical 3 torsion Π 372 810 439 0.459
HOCO Hydrocarboxyl radical 1 A' 3316 3819 503 0.868
CHCl2 dichloromethyl radical 4 A' 190 320 130 0.594
CH2Cl chloromethyl radical 4 B1 402 -147 -549 -2.726
HNC+ hydrogen isocyanide cation 2 Σ 2195 2683 488 0.818
HN3+ Hydrazoic acid cation 2 A' 1850 2987 1137 0.619
CaBr2 Calcium dibromide 3 Πu 72 37 -35 1.938
HOCl+ hypochlorous acid cation 3 A' 830 1202 372 0.691
O3 Ozone 3 B2 1042 1760 718 0.592
NO Nitric oxide 1 Σ 1876 2803 927 0.669
NO2 Nitrogen dioxide 3 B2 1618 2261 643 0.716
AsSe Arsenic monoselenide 1 Σ 280 429 149 0.652
NS Mononitrogen monosulfide 1 Σ 1204 1746 542 0.690
Li2O dilithium oxide 3 Πu 112 92 -20 1.215
C3 carbon trimer 3 Πu 63 118 55 0.537
S3 Sulfur trimer 2 A1 281 583 302 0.482
SiH2D2 silane-d2 6 B1 2183 1686 -497 1.295
SiH2D2 silane-d2 8 B2 1601 2332 731 0.686
PO Phosphorus monoxide 1 Σ 1220 2147 927 0.568
NH4 Ammonium radical 1 A1 2552 2955 403 0.864
B5H9 pentaborane9 13 B1 240 619 379 0.388
B5H9 pentaborane9 16 B2 1036 816 -220 1.270
B5H9 pentaborane9 18 B2 600 486 -114 1.234
B5H9 pentaborane9 22 E 1409 1112 -297 1.268
OPCl Phosphorus oxychloride 2 A' 308 504 196 0.611
OPCl Phosphorus oxychloride 3 A' 492 323 -169 1.524
CHFCl Chlorofluoromethyl radical 6 A 540 422 -118 1.280
H2CNCN cyanamide, methylene 3 A' 2208 3142 934 0.703
H2CNCN cyanamide, methylene 4 A' 1621 2411 790 0.672
SNO Nitrogen oxide sulfide 1 A' 1527 1974 446 0.774
SNO Nitrogen oxide sulfide 3 A' 792 537 -255 1.474
ONNO NO dimer 3 A1 135 263 128 0.512
ONNO NO dimer 4 torsion A2 117 244 127 0.480
ONNO NO dimer 6 B2 429 652 223 0.658
ClONO chlorine nitrite 4 A' 406 620 214 0.655
NSO sulfinyl amidogen 2 A' 1010 829 -181 1.218