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 QCISD/6-31G**
Calculated values were scaled by 0.9414.

Species Name mode Symmetry Experiment Theory difference ratio
CH3SeH Methane selenol 12 A" 145 210 65 0.692
C3H4O2 β–Propiolactone 21 A" 113 164 51 0.688
CH3OH Methyl alcohol 12 A" 200 321 121 0.623
CH3COCH3 Acetone 12 A2 77 49 -28 1.575
C2Cl6 hexachloroethane 12 Eu 114 163 49 0.700
C6H6 Benzene 8 B2g 703 539 -164 1.303
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 307 93 0.698
C2H4+ Ethylene cation 4 Au 84 -202 -287 -0.415
C2H2 Acetylene 4 Πg 612 438 -174 1.397
CHONH2 formamide 12 A" 289 -139 -428 -2.073
C3F8 perfluoropropane 13 A2 276 212 -64 1.301
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 54 -21 1.388
CH3COOCH3 methyl acetate 27 A" 110 70 -40 1.570
C10H8 naphthalene 27 B2g 770 424 -346 1.817
C6H5NO2 Nitrobenzene 22 B1 675 521 -154 1.297
C6H5CHO benzaldehyde 32 A" 688 537 -151 1.281
C6H4O2 parabenzoquinone 17 B2g 241 173 -68 1.390
C6H4O2 parabenzoquinone 30 B3u 109 81 -27 1.336
C3H6O 2-Propen-1-ol 24 A 188 105 -83 1.794
C6H5Cl chlorobenzene 18 B1 685 530 -155 1.292
C5H12 Pentane 23 A2 131 101 -30 1.295
C4H8S Thiophene, tetrahydro- 5 A 1464 2951 1487 0.496
C4H8S Thiophene, tetrahydro- 6 A 1441 2951 1510 0.488
C4H8S Thiophene, tetrahydro- 7 A 1321 2932 1611 0.451
C4H8S Thiophene, tetrahydro- 8 A 1276 2931 1655 0.435
C4H8S Thiophene, tetrahydro- 11 A 1023 1453 430 0.704
C4H8S Thiophene, tetrahydro- 12 A 888 1450 562 0.612
C4H8S Thiophene, tetrahydro- 13 A 829 1331 502 0.623
C4H8S Thiophene, tetrahydro- 14 A 822 1308 486 0.628
C4H8S Thiophene, tetrahydro- 15 A 678 1286 608 0.527
C4H8S Thiophene, tetrahydro- 16 A 472 1257 785 0.375
C4H8S Thiophene, tetrahydro- 17 A 290 1209 919 0.240
C5H8 Cyclopentene 18 A' 254 159 -95 1.593
NH2CN cyanamide 5 A' 408 636 228 0.642
C4H6O2 2,3-Butanedione 21 Bg 240 113 -127 2.121
C6H5F Fluorobenzene 18 B1 685 530 -155 1.292
C2H3NO3 Oxamic acid 3 A' 2600 3481 881 0.747
C2H3NO3 Oxamic acid 16 A" 984 758 -226 1.298
C2H3NO3 Oxamic acid 21 A" 162 42 -120 3.889
C3H6O Oxetane 18 B1 90 -53 -143 -1.702
HCNO fulminic acid 5 Π 224 -102 -326 -2.199
C6H4F2 1,4-difluorobenzene 16 B2g 692 514 -178 1.346
C5H8 1,4-Pentadiene 16 A 137 283 146 0.483
HCCCl Chloroacetylene 5 Π 326 231 -95 1.409
C6H6 Benzvalene 10 A1 996 747 -249 1.333
C2F2 difluoroacetylene 4 Πg 270 195 -75 1.384
H2CS- thioformaldehyde anion 4 B1 450 -160 -610 -2.816
GeO2 Germanium dioxide 3 Πu 196 150 -45 1.300
NaOH sodium hydroxide 3 Π 300 99 -201 3.029
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 213 69 0.675
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 329 -127 1.386
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 107 -64 1.601
CH3 Methyl radical 2 A2" 606 395 -212 1.536
CH2OH Hydroxymethyl radical 8 A 482 710 228 0.679
CH2OH Hydroxymethyl radical 9 A 234 421 187 0.556
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 856 -280 1.327
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 117 -147 2.248
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 85 -273 4.191
HCCN cyanomethylene 5 Π 129 -486 -615 -0.265
CHCl2 dichloromethyl radical 4 A' 190 295 105 0.644
C4H6 Methylenecyclopropane 17 B1 360 263 -97 1.367
C2Cl2 dichloroacetylene 4 Πg 333 178 -155 1.874
HClO4 perchloric acid 12 A" 191 143 -48 1.333
CuCl Copper monochloride 1 Σ 418 263 -155 1.588
FOOF Perfluoroperoxide 1 A 1210 946 -264 1.280
OClO- Chlorine dioxide anion 2 A1 418 319 -99 1.311
N2O3 Dinitrogen trioxide 9 A" 63 133 70 0.474
Li2O dilithium oxide 3 Πu 112 42 -69 2.647
C3 carbon trimer 3 Πu 63 47 -17 1.354
TiO Titanium monoxide 1 Σ 1009 4403 3394 0.229
C4 Carbon tetramer 4 Πg 323 252 -71 1.282
CuF Copper monofluoride 1 Σ 623 471 -151 1.321
CuH Copper monohydride 1 Σ 1941 613 -1329 3.168
ZnH2 Zinc hydride 3 Πu 633 462 -171 1.370
Cl3- trichloride anion 2 Σu 327 219 -108 1.493
CaS Calcium sulfide 1 Σ 462 359 -103 1.287
OPCl Phosphorus oxychloride 2 A' 308 482 174 0.638
OPCl Phosphorus oxychloride 3 A' 492 294 -198 1.676
H2POH Phosphinous acid 9 A" 375 252 -124 1.491
Mg2 Magnesium diatomic 1 Σg 51 14 -38 3.758
ZnCH3 Zinc monomethyl 6 E 315 594 279 0.530
ZnCN Zinc monocyanide 3 Π 212 80 -132 2.636