return to home page Computational Chemistry Comparison and Benchmark DataBase Release 18 (October 2016) Standard Reference Database 101 National Institute of Standards and Technology
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Bad vibrational frequency predictions

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=FULL/6-31G(2df,p)
Calculated values were scaled by 0.9423.

Species Name mode Symmetry Experiment Theory difference ratio
CH3SeH Methane selenol 12 A" 145 228 83 0.635
CH3CONH2 Acetamide 20 A 259 185 -74 1.400
CH3OH Methyl alcohol 12 A" 200 319 119 0.627
C2H4+ Ethylene cation 4 Au 84 -119 -203 -0.705
C2H2 Acetylene 4 Πg 612 477 -135 1.284
CHONH2 formamide 12 A" 289 98 -191 2.955
CBr2F2 Methane, dibromodifluoro- 3 A1 140 346 206 0.404
CBr2F2 Methane, dibromodifluoro- 9 B2 235 337 102 0.698
C3F8 perfluoropropane 13 A2 276 214 -62 1.292
CF2CCl2 difluorodichloroethylene 7 B1 1327 611 -716 2.171
CF2CCl2 difluorodichloroethylene 8 B1 989 314 -675 3.150
CF2CCl2 difluorodichloroethylene 12 B2 323 178 -145 1.817
C3H6O 2-Propen-1-ol 24 A 188 108 -81 1.749
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 6 A2 351 548 197 0.640
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 8 B1 1209 343 -866 3.520
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 12 B2 533 402 -131 1.326
CH2NN diazomethane 6 B1 406 131 -275 3.093
C6F6 hexafluorobenzene 8 B2g 243 180 -63 1.351
C6F6 hexafluorobenzene 20 E2u 175 134 -41 1.309
NH2CN cyanamide 5 A' 408 634 226 0.644
C4H6O2 2,3-Butanedione 21 Bg 240 127 -113 1.896
C3H6O Oxetane 18 B1 90 -77 -166 -1.173
CO+ carbon monoxide cation 1 Σ 2214 2692 478 0.822
C2F2 difluoroacetylene 4 Πg 270 453 183 0.596
SiF2+ Silicon difluoride cation 2 A1 350 269 -81 1.300
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.681
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 343 -113 1.329
CN Cyano radical 1 Σ 2069 2728 660 0.758
C2H Ethynyl radical 2 Σ 1841 2388 547 0.771
C2H Ethynyl radical 3 Π 372 823 452 0.451
C2H+ Ethynyl cation 3 Π 550 810 260 0.679
CH3 Methyl radical 2 A2" 606 372 -234 1.629
CH2OH Hydroxymethyl radical 8 A 482 693 211 0.696
CH2OH Hydroxymethyl radical 9 A 234 431 197 0.543
CHCl2 dichloromethyl radical 4 A' 190 296 106 0.642
CH2CHO Vinyloxy radical 10 A" 703 1028 325 0.684
O2+ diatomic oxygen cation 1 Σg 1906 1422 -484 1.340
GaF3 Gallium trifluoride 4 E' 192 93 -99 2.062
D2O Deuterium oxide 1 A1 2671 3666 995 0.729
D2O Deuterium oxide 2 A1 1178 1600 422 0.736
D2O Deuterium oxide 3 B2 2788 3785 997 0.737
CaF2 Calcium difluoride 2 A1 120 84 -36 1.428
O3 Ozone 3 B2 1042 2076 1034 0.502
NO Nitric oxide 1 Σ 1904 3195 1291 0.596
NO2 Nitrogen dioxide 3 B2 1618 4523 2905 0.358
N2O3 Dinitrogen trioxide 9 A" 63 169 106 0.372
VO Vanadium monoxide 1 Σ 1011 1915 903 0.528
C3 carbon trimer 3 Πu 63 218 154 0.291
SiP Silicon monophosphide 1 Σ 616 1011 396 0.609
CaOH Calcium monohydroxide 2 Σ 353 616 263 0.573
CaOH Calcium monohydroxide 3 Π 609 372 -237 1.636
Cu2 Copper dimer 1 Σg 265 417 153 0.634
PS phosphorus sulfide 1 Σ 739 1063 324 0.695
DS Mercapto-d 1 Σ 1886 2628 743 0.717
SF5Cl sulfur chloropentafluoride 5 B1 625 477 -148 1.311
SF5Cl sulfur chloropentafluoride 7 B2 505 325 -180 1.556
SF5Cl sulfur chloropentafluoride 11 E 397 257 -140 1.543
C2H4O4 Formic acid dimer 13 Au 1050 69 -981 15.158
PN+ phosphorus nitride cation 1 Σ 1200 1607 407 0.747
H2OH2O water dimer 12 A" 88 50 -38 1.756
H2POH Phosphinous acid 9 A" 375 264 -111 1.419
ZnCH3 Zinc monomethyl 6 E 315 598 283 0.527
CH3BO Borane, methyloxo- 7 E 897 1412 515 0.635
ONONO Nitrosyl nitrite 9 B2 380 298 -82 1.274