return to home page Computational Chemistry Comparison and Benchmark DataBase Release 19 (April 2018) 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 MP4/6-31G*
Calculated values were scaled by 0.9548.

Species Name mode Symmetry Experiment Theory difference ratio
CH3SeH Methane selenol 12 A" 145 207 62 0.699
CH3OH Methyl alcohol 12 A" 200 335 135 0.598
CH3COCH3 Acetone 12 A2 77 56 -21 1.378
C2H4+ Ethylene cation 4 Au 84 -164 -248 -0.512
C2H2 Acetylene 4 Πg 612 299 -313 2.049
HCN+ hydrogen cyanide cation 1 Σ 3050 3547 497 0.860
HCN+ hydrogen cyanide cation 2 Σ 1800 2741 941 0.657
CH3CCH propyne 9 E 633 470 -163 1.346
CH3CCH propyne 10 E 328 198 -130 1.654
CHONH2 formamide 12 A" 289 -191 -480 -1.509
CH3COCl Acetyl Chloride 15 A" 166 123 -43 1.355
CH3COOCH3 methyl acetate 27 A" 110 50 -60 2.193
C10H8 naphthalene 27 B2g 770 418 -352 1.844
C10H8 naphthalene 28 B2g 461 248 -213 1.857
C6H4O2 parabenzoquinone 17 B2g 241 172 -69 1.400
C6H4O2 parabenzoquinone 30 B3u 109 84 -24 1.285
CHCCH2CH3 1-Butyne 22 A" 630 476 -154 1.324
C3H6O 2-Propen-1-ol 24 A 188 106 -82 1.767
C3H2N2 Malononitrile 6 A1 167 132 -35 1.270
CH2NN diazomethane 6 B1 406 207 -199 1.960
NH2CN cyanamide 5 A' 408 673 265 0.606
C4H6O2 2,3-Butanedione 21 Bg 240 112 -128 2.137
C4H2 Diacetylene 7 Πg 482 -107 -589 -4.522
C4H2 Diacetylene 8 Πu 630 397 -233 1.589
F2CCCF2 tetrafluoroallene 5 B2 2052 686 -1366 2.992
F2CCCF2 tetrafluoroallene 6 B2 1030 538 -492 1.915
F2CCCF2 tetrafluoroallene 7 B2 581 366 -215 1.587
F2CCCF2 tetrafluoroallene 11 E 90 64 -26 1.407
C6H5F Fluorobenzene 18 B1 685 504 -181 1.358
C3H6O Oxetane 18 B1 90 -79 -169 -1.132
HCNO fulminic acid 5 Π 224 -436 -660 -0.514
C6H4F2 1,4-difluorobenzene 16 B2g 692 489 -203 1.415
C5H8 1,4-Pentadiene 16 A 137 286 149 0.479
C5H8 1,4-Pentadiene 17 A 102 78 -24 1.301
HCCCl Chloroacetylene 4 Π 604 471 -133 1.282
HCCCl Chloroacetylene 5 Π 326 124 -202 2.619
CO+ carbon monoxide cation 1 Σ 2214 2628 414 0.843
C6H6 Benzvalene 10 A1 996 741 -255 1.343
C2F2 difluoroacetylene 4 Πg 270 66 -204 4.067
H2CS- thioformaldehyde anion 4 B1 450 -183 -633 -2.458
BeO beryllium oxide 1 Σ 1457 575 -883 2.536
CaO Calcium monoxide 1 Σ 732 1353 621 0.541
MgO magnesium oxide 1 Σ 785 1173 388 0.669
GeO2 Germanium dioxide 3 Πu 196 140 -55 1.394
NaOH sodium hydroxide 3 Π 300 89 -211 3.390
ZnO zinc monoxide 1 Σ 720 1032 312 0.698
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 216 72 0.667
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 329 -127 1.386
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 113 -58 1.508
FCO+ Carbonyl fluoride cation 3 Π 650 493 -157 1.318
CN Cyano radical 1 Σ 2069 2567 498 0.806
C2H Ethynyl radical 2 Σ 1841 2298 457 0.801
C2H Ethynyl radical 3 Π 372 720 348 0.516
CH3 Methyl radical 2 A2" 606 399 -207 1.518
CH2OH Hydroxymethyl radical 8 A 482 726 244 0.664
CH2OH Hydroxymethyl radical 9 A 234 436 202 0.536
HCCN cyanomethylene 5 Π 129 -497 -626 -0.259
HCCF Fluoroacetylene 5 Π 367 277 -90 1.324
CHCl2 dichloromethyl radical 4 A' 190 299 109 0.635
C4H6 Methylenecyclopropane 17 B1 360 260 -100 1.387
TiCl4 Titanium tetrachloride 1 A1 389 164 -225 2.373
PCl3 Phosphorus trichloride 3 E 482 176 -306 2.734
PCl3 Phosphorus trichloride 4 E 198 488 290 0.406
O2+ diatomic oxygen cation 1 Σg 1906 1442 -464 1.322
FOOF Perfluoroperoxide 1 A 1210 953 -257 1.270
O3 Ozone 3 B2 1042 1530 488 0.681
SiO Silicon monoxide 1 Σ 1242 937 -304 1.325
NO Nitric oxide 1 Σ 1904 3632 1727 0.524
NO+ nitric oxide cation 1 Σ 2377 1826 -551 1.302
NO2 Nitrogen dioxide 1 A1 1318 10672 9354 0.124
NO2 Nitrogen dioxide 2 A1 750 -4757 -5507 -0.158
NO2 Nitrogen dioxide 3 B2 1618 17080 15462 0.095
N2O3 Dinitrogen trioxide 5 A' 627 472 -155 1.327
N2O3 Dinitrogen trioxide 7 A' 205 156 -49 1.310
N2O3 Dinitrogen trioxide 9 A" 63 156 93 0.404
C3O Tricarbon monoxide 5 Π 109 160 51 0.683
NS+ nitrogen sulfide cation 1 Σ 1415 1009 -406 1.402
VO Vanadium monoxide 1 Σ 1011 2329 1318 0.434
ScO Scandium monoxide 1 Σ 965 739 -226 1.305
FO Oxygen monofluoride 1 Σ 1053 2519 1466 0.418
C3 carbon trimer 3 Πu 63 169 105 0.376
TiO Titanium monoxide 1 Σ 1009 1655 646 0.610
Cu2 Copper dimer 1 Σg 265 405 140 0.653
ClNO2 Nitryl chloride 3 A1 364 267 -97 1.365
TiO2 Titanium dioxide 1 A1 959 2885 1926 0.332
TiO2 Titanium dioxide 3 B2 944 2120 1176 0.445
ZnH2 Zinc hydride 3 Πu 633 473 -159 1.336
PO+ phosphorus monoxide cation 1 Σ 1405 841 -564 1.671
AlO Aluminum monoxide 1 Σ 979 10184 9204 0.096
ClONO2 Chlorine nitrate 6 A' 434 340 -94 1.275
ClOO chloroperoxy radical 2 A' 414 1031 617 0.401
ClOO chloroperoxy radical 3 A' 201 478 277 0.421
GeO Germanium monoxide 1 Σ 986 501 -484 1.966
OPCl Phosphorus oxychloride 2 A' 308 467 159 0.659
OPCl Phosphorus oxychloride 3 A' 492 280 -212 1.755
H2OH2O water dimer 11 A" 108 156 48 0.693
F3- trifluoride anion 1 Σg 461 333 -128 1.384
H2POH Phosphinous acid 9 A" 375 252 -124 1.491
AsN Arsenic mononitride 1 Σ 1069 719 -350 1.486
Mg2 Magnesium diatomic 1 Σg 51 234 183 0.219
BrONO2 Bromine nitrate 5 A' 564 428 -136 1.318
ZnCH3 Zinc monomethyl 6 E 315 607 292 0.519
ZnCN Zinc monocyanide 3 Π 212 -61 -273 -3.491
BrONO Bromine nitrite 4 A' 391 304 -87 1.288
ONONO Nitrosyl nitrite 9 B2 380 235 -145 1.618