return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
You are here: Calculated > Vibrations > Bad Calculations > Bad vib. Calc. vs exp. OR Resources > Bad Calculations > Vibrations > Bad vib. Calc. vs exp.

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 MP2/aug-cc-pVDZ
Calculated values were scaled by 0.959.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3CONH2 Acetamide 20 A 259 89 -170 2.904
CH3OH Methyl alcohol 12 torsion A" 200 299 99 0.669
C2H6O2S Dimethyl sulfone 20 B1 262 195 -67 1.340
C6H6 Benzene 8 B2g 703 553 -150 1.272
C2H4+ Ethylene cation 4 torsion Au 84 -100 -184 -0.842
C2H2 Acetylene 4 Πg 612 391 -221 1.563
HCN+ hydrogen cyanide cation 1 Σ 3050 3784 734 0.806
HCN+ hydrogen cyanide cation 2 Σ 1800 2789 989 0.645
CH3CCH propyne 10 E 328 254 -74 1.292
CHONH2 formamide 12 torsion A" 289 167 -122 1.727
CH3COOCH3 methyl acetate 27 torsion A" 110 47 -63 2.348
C6H4Cl2 1,2-dichlorobenzene 14 A2 695 522 -173 1.332
C6H4Cl2 1,4-dichlorobenzene 16 B2g 687 533 -154 1.289
C6H4Cl2 1,4-dichlorobenzene 30 B3u 122 97 -25 1.264
CH3CH2CH2CH3 Butane 5 Ag 1442 408 -1034 3.533
CH3CH2CH2CH3 Butane 8 Ag 1151 817 -334 1.408
CH3CH2CH2CH3 Butane 36 Bu 271 3021 2750 0.090
C3H6O 2-Propen-1-ol 24 A 188 107 -81 1.757
C3H2N2 Malononitrile 6 A1 167 132 -35 1.261
CHSNH2 thioformamide 12 A" 393 307 -86 1.282
C3F6 hexafluoropropene 21 A" 60 39 -21 1.530
C6F6 hexafluorobenzene 7 B2g 719 447 -272 1.610
NH2CN cyanamide 5 torsion A' 408 644 236 0.634
C4H6O2 2,3-Butanedione 21 torsion Bg 240 125 -115 1.922
C4H2 Diacetylene 7 Πg 482 -626 -1108 -0.770
C4H2 Diacetylene 8 Πu 630 488 -142 1.292
C4H2 Diacetylene 9 Πu 231 145 -86 1.593
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 988 -403 1.407
F2CCCF2 tetrafluoroallene 11 E 90 63 -27 1.428
C2H3NO3 Oxamic acid 3 A' 2600 3452 852 0.753
C2H3NO3 Oxamic acid 15 A' 328 258 -70 1.272
C2H3NO3 Oxamic acid 17 A" 815 643 -172 1.267
C2H3NO3 Oxamic acid 21 A" 162 61 -101 2.657
CH3CCCH3 2-Butyne 16 E" 371 210 -161 1.763
C3H6O Oxetane 18 B1 90 -96 -186 -0.933
C3H6O Oxetane 23 B2 1228 980 -248 1.254
C3O2 Carbon suboxide 7 Πu 61 -92 -153 -0.662
HCNO fulminic acid 5 torsion Π 224 -350 -574 -0.641
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 648 -2431 4.753
C5H8 1,4-Pentadiene 16 A 137 291 154 0.471
HCCCl Chloroacetylene 5 Π 326 244 -82 1.336
P(CH3)3 trimethylphosphine 22 E 259 199 -60 1.300
CH3ONO Methyl nitrite 15 torsion A" 186 75 -111 2.468
CH3SSCH3 Disulfide, dimethyl 13 torsion A 117 91 -26 1.292
CO+ carbon monoxide cation 1 Σ 2184 2732 548 0.799
C6H6 Benzvalene 10 A1 996 725 -271 1.375
H2CS- thioformaldehyde anion 4 B1 450 262 -188 1.715
CH2ClCCCl 1,3-dichloropropyne 14 A" 337 220 -117 1.530
HCCCN Cyanoacetylene 7 Π 222 167 -55 1.327
SiF2+ Silicon difluoride cation 2 A1 350 274 -76 1.276
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.675
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 336 -120 1.357
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 134 -37 1.277
CH2NH+ Methanimine cation 4 A' 1370 1813 443 0.756
CN Cyano radical 1 Σ 2042 2722 680 0.750
C2H Ethynyl radical 2 Σ 1841 2346 506 0.784
C2H Ethynyl radical 3 torsion Π 372 721 350 0.515
CH3OO methylperoxy radical 12 torsion A" 170 127 -43 1.335
CH3 Methyl radical 2 torsion A2" 606 474 -132 1.278
CH2OH Hydroxymethyl radical 9 torsion A 234 421 187 0.556
HCCN cyanomethylene 5 Π 129 -548 -677 -0.235
CCl3 Trichloromethyl radical 2 A1 251 366 115 0.686
CHCl2 dichloromethyl radical 4 A' 190 295 105 0.643
C4H6 Methylenecyclopropane 17 B1 360 252 -108 1.429
CH2Cl chloromethyl radical 4 B1 402 -204 -606 -1.967
HNC+ hydrogen isocyanide cation 2 Σ 2195 2679 483 0.820
C2Cl2 dichloroacetylene 4 Πg 333 111 -222 2.987
BF3+ boron trifluoride cation 5 B2 1791 3123 1332 0.573
O2+ diatomic oxygen cation 1 Σg 1873 1391 -482 1.346
HN3+ Hydrazoic acid cation 2 A' 1850 3186 1336 0.581
FOOF Perfluoroperoxide 1 A 1210 1716 506 0.705
FOOF Perfluoroperoxide 3 A 360 255 -105 1.412
FOOF Perfluoroperoxide 4 torsion A 202 138 -64 1.468
HOCl+ hypochlorous acid cation 3 A' 830 1250 420 0.664
O3 Ozone 3 B2 1042 2189 1147 0.476
NO Nitric oxide 1 Σ 1876 3517 1641 0.533
NO2 Nitrogen dioxide 3 B2 1618 2394 776 0.676
N2O3 Dinitrogen trioxide 9 torsion A" 63 160 97 0.393
C3O Tricarbon monoxide 5 Π 109 83 -26 1.312
AsSe Arsenic monoselenide 1 Σ 280 400 120 0.700
GaO Gallium monoxide 1 Σ 755 561 -194 1.345
NaO2 Sodium superoxide 3 B2 333 1315 982 0.253
VO Vanadium monoxide 1 Σ 1002 2112 1111 0.474
FO Oxygen monofluoride 1 Σ 1033 2244 1211 0.460
SiC2 Silicon dicarbide 3 B2 196 -163 -359 -1.207
C3 carbon trimer 3 Πu 63 -47 -110 -1.361
LiO2 Lithium dioxide 3 B2 509 1326 817 0.384
C4 Carbon tetramer 4 Πg 323 -129 -452 -2.502
C4 Carbon tetramer 5 Πu 160 126 -34 1.270
SiH2D2 silane-d2 6 B1 2183 1577 -606 1.384
SiH2D2 silane-d2 8 B2 1601 2182 581 0.734
AlO Aluminum monoxide 1 Σ 965 626 -339 1.542
GeF Germanium monofluoride 1 Σ 809 618 -191 1.309
SCN thiocyanato radical 1 Σ 1942 2419 477 0.803
ClOO chloroperoxy radical 2 A' 414 1044 631 0.396
ClOO chloroperoxy radical 3 A' 201 485 283 0.416
B4H10 Tetraborane(10) 10 A1 827 656 -171 1.261
B4H10 Tetraborane(10) 11 A1 785 562 -223 1.396
B4H10 Tetraborane(10) 12 A1 559 222 -337 2.518
B4H10 Tetraborane(10) 19 A2 662 395 -267 1.674
B4H10 Tetraborane(10) 36 B2 236 344 108 0.685
FSN Thiazyl fluoride 3 A' 366 283 -83 1.291
B5H9 pentaborane9 13 B1 240 590 350 0.407
B5H9 pentaborane9 16 B2 1036 764 -272 1.356
B5H9 pentaborane9 18 B2 600 462 -138 1.300
B5H9 pentaborane9 22 E 1409 1030 -379 1.367
OPCl Phosphorus oxychloride 2 A' 308 458 150 0.672
OPCl Phosphorus oxychloride 3 A' 492 273 -219 1.800
NCO isocyanato radical 1 Σ 1921 2375 454 0.809
S2N2 Disulfur dinitride 1 Ag 913 730 -183 1.251
H2POH Phosphinous acid 9 A" 375 245 -130 1.531
AsN Arsenic mononitride 1 Σ 1058 809 -249 1.308
Mg2 Magnesium diatomic 1 Σg 48 27 -21 1.787
ClOF3 Chlorine trifluoride oxide 5 A' 319 244 -75 1.308
ClOF3 Chlorine trifluoride oxide 9 A" 412 313 -99 1.318
CHFCl Chlorofluoromethyl radical 6 A 540 390 -150 1.384
BrONO2 Bromine nitrate 5 A' 564 440 -124 1.282
H2CNCN cyanamide, methylene 3 A' 2208 2994 786 0.737
H2CNCN cyanamide, methylene 4 A' 1621 2052 431 0.790
SNO Nitrogen oxide sulfide 3 A' 792 519 -273 1.526
ONNO NO dimer 3 A1 135 305 171 0.441
ONNO NO dimer 4 torsion A2 117 271 154 0.431
AlNC Aluminum isocyanide 3 Π 100 72 -28 1.384
ClONO chlorine nitrite 4 A' 406 297 -109 1.369
BrONO Bromine nitrite 4 A' 391 293 -99 1.337
ONONO Nitrosyl nitrite 9 B2 380 -148 -528 -2.564