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 CCSD(T)/6-31G*
Calculated values were scaled by 0.9621.

Species Name mode Symmetry Experiment Theory difference ratio
CH3SeH Methane selenol 12 A" 145 208 63 0.698
CH3OH Methyl alcohol 12 A" 200 335 135 0.596
C6H6 Benzene 8 B2g 703 515 -188 1.366
CH3CCl3 Ethane, 1,1,1-trichloro- 6 A2 214 308 94 0.695
C2H4+ Ethylene cation 4 Au 84 -276 -360 -0.305
C2H2 Acetylene 4 Πg 612 319 -293 1.919
CH3CCH propyne 9 E 633 482 -151 1.312
CH3CCH propyne 10 E 328 213 -115 1.542
CHONH2 formamide 12 A" 289 -201 -490 -1.437
C10H8 naphthalene 27 B2g 770 420 -350 1.832
C10H8 naphthalene 28 B2g 461 289 -172 1.595
C6H5CN phenyl cyanide 19 B1 688 538 -150 1.278
C6H4O2 parabenzoquinone 17 B2g 241 178 -63 1.352
CHCCH2CH3 1-Butyne 22 A" 630 490 -140 1.285
C3H6O 2-Propen-1-ol 24 A 188 106 -82 1.776
C3H2N2 Malononitrile 6 A1 167 133 -34 1.252
CH2NN diazomethane 6 B1 406 317 -89 1.282
NH2CN cyanamide 5 A' 408 678 270 0.602
C4H2 Diacetylene 7 Πg 482 105 -377 4.597
C4H2 Diacetylene 8 Πu 630 424 -206 1.486
F2CCCF2 tetrafluoroallene 5 B2 2052 696 -1356 2.946
F2CCCF2 tetrafluoroallene 6 B2 1030 545 -485 1.891
F2CCCF2 tetrafluoroallene 7 B2 581 371 -210 1.565
F2CCCF2 tetrafluoroallene 11 E 90 65 -25 1.392
C3H6O Oxetane 18 B1 90 -71 -161 -1.270
HCNO fulminic acid 5 Π 224 -275 -499 -0.814
HCCCl Chloroacetylene 5 Π 326 156 -170 2.086
C6H6 Benzvalene 10 A1 996 749 -247 1.330
C2F2 difluoroacetylene 4 Πg 270 114 -156 2.362
H2CS- thioformaldehyde anion 4 B1 450 -170 -620 -2.648
HCCCN Cyanoacetylene 6 Π 499 398 -101 1.254
GeO2 Germanium dioxide 3 Πu 196 145 -51 1.352
NaOH sodium hydroxide 3 Π 300 119 -181 2.527
FCO+ Carbonyl fluoride cation 3 Π 650 517 -133 1.258
C2H Ethynyl radical 3 Π 372 296 -76 1.256
CH3 Methyl radical 2 A2" 606 416 -191 1.459
CH2OH Hydroxymethyl radical 8 A 482 715 233 0.674
CH2OH Hydroxymethyl radical 9 A 234 435 201 0.538
HCCN cyanomethylene 5 Π 129 -504 -633 -0.256
C2H3+ vinyl cation 2 A1 2217 2931 714 0.756
HCCF Fluoroacetylene 5 Π 367 287 -80 1.279
CHCl2 dichloromethyl radical 4 A' 190 299 109 0.635
C2Cl2 dichloroacetylene 4 Πg 333 80 -253 4.187
OClO- Chlorine dioxide anion 2 A1 418 318 -100 1.315
N2O3 Dinitrogen trioxide 9 A" 63 143 80 0.441
SF5 Sulfur pentafluoride 2 A1 633 502 -131 1.260
SF5 Sulfur pentafluoride 7 E 818 629 -189 1.300
Li2O dilithium oxide 3 Πu 112 50 -62 2.253
C4 Carbon tetramer 4 Πg 323 235 -88 1.374
ZnH2 Zinc hydride 3 Πu 633 477 -156 1.327
ClOO chloroperoxy radical 3 A' 201 119 -83 1.698
Cl3- trichloride anion 2 Σu 327 261 -66 1.255
CaS Calcium sulfide 1 Σ 462 370 -92 1.249
OPCl Phosphorus oxychloride 2 A' 308 487 179 0.632
OPCl Phosphorus oxychloride 3 A' 492 294 -198 1.672
H2OH2O water dimer 11 A" 108 154 46 0.700
H2POH Phosphinous acid 9 A" 375 250 -126 1.503
Mg2 Magnesium diatomic 1 Σg 51 15 -36 3.318
ZnCH3 Zinc monomethyl 6 E 315 603 288 0.523
ZnCN Zinc monocyanide 3 Π 212 57 -155 3.722