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 B3LYPultrafine/6-31G*
Calculated values were scaled by 0.958.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 178 65 0.636
CH3CONH2 Acetamide 20 A 259 130 -129 1.998
CH3OH Methyl alcohol 12 A" 200 332 132 0.603
CH3COCH3 Acetone 12 A2 77 47 -30 1.623
C2H6O2S Dimethyl sulfone 20 B1 262 201 -61 1.301
C2H4+ Ethylene cation 4 Au 84 -417 -502 -0.201
CHONH2 formamide 12 A" 289 79 -210 3.656
CBr2F2 Methane, dibromodifluoro- 3 A1 140 313 173 0.448
C2F6 hexafluoroethane 4 A1u 68 50 -18 1.361
C3F8 perfluoropropane 13 A2 276 210 -66 1.316
CH3COOCH3 methyl acetate 27 A" 110 54 -56 2.029
CF2CCl2 difluorodichloroethylene 7 B1 1327 566 -761 2.343
CF2CCl2 difluorodichloroethylene 8 B1 989 311 -678 3.178
CF2CCl2 difluorodichloroethylene 11 B2 564 437 -127 1.290
CF2CCl2 difluorodichloroethylene 12 B2 323 180 -143 1.793
C3H6O 2-Propen-1-ol 24 A 188 111 -77 1.692
C5H8 Cyclopentene 18 A' 254 135 -119 1.882
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 6 A2 351 504 153 0.696
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 8 B1 1209 331 -878 3.653
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 12 B2 533 395 -138 1.349
CF3CN Acetonitrile, trifluoro- 4 A1 522 2297 1775 0.227
NH2CN cyanamide 5 A' 408 584 176 0.699
C4H6O2 2,3-Butanedione 21 Bg 240 105 -135 2.288
C2H3NO3 Oxamic acid 3 A' 2600 3445 845 0.755
C2H3NO3 Oxamic acid 15 A' 328 258 -70 1.271
C2H3NO3 Oxamic acid 16 A" 984 783 -201 1.256
C2H3NO3 Oxamic acid 21 A" 162 64 -98 2.529
C3O2 Carbon suboxide 7 Πu 61 124 63 0.493
C3H6O Oxetane 18 B1 90 68 -22 1.322
C5H8 1,4-Pentadiene 16 A 137 287 150 0.477
C2F2 difluoroacetylene 4 Πg 270 194 -76 1.394
SiF2+ Silicon difluoride cation 2 A1 350 279 -71 1.255
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 212 68 0.679
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 345 -111 1.323
CH3OO methylperoxy radical 12 A" 170 135 -35 1.261
CH3 Methyl radical 2 A2" 606 435 -172 1.396
C4H9N Cyclobutylamine 21 A' 174 137 -37 1.268
CH2OH Hydroxymethyl radical 9 A 234 432 198 0.542
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 863 -273 1.316
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 155 -109 1.707
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 103 -255 3.483
CHCl2 dichloromethyl radical 4 A' 190 292 102 0.650
C4H6 Methylenecyclopropane 17 B1 360 282 -78 1.278
HClO4 perchloric acid 12 A" 191 150 -41 1.274
ZnCN Zinc monocyanide 3 Π 212 51 -161 4.151
PCl5 Phosphorus pentachloride 2 A1' 370 256 -114 1.444
N2O3 Dinitrogen trioxide 9 A" 63 140 77 0.451
C3 carbon trimer 3 Πu 63 177 114 0.357
SF5 Sulfur pentafluoride 9 E 387 305 -82 1.268
SiH- silicon monohydride anion 1 Σ 2175 1728 -447 1.258
ZnH2 Zinc hydride 3 Πu 633 497 -136 1.274
ClOO chloroperoxy radical 3 A' 201 123 -79 1.643
ClOO chloroperoxy radical 2 A' 414 298 -116 1.388
SF5Cl sulfur chloropentafluoride 11 E 397 231 -166 1.719
SF5Cl sulfur chloropentafluoride 7 B2 505 295 -210 1.713
SF5Cl sulfur chloropentafluoride 5 B1 625 439 -186 1.425
C2H4O4 Formic acid dimer 13 Au 1050 72 -978 14.515
H2OH2O water dimer 6 A' 311 446 135 0.698
H2OH2O water dimer 7 A' 143 224 81 0.638
H2OH2O water dimer 11 A" 108 166 58 0.649
H2OH2O water dimer 12 A" 88 -59 -147 -1.485
H2POH Phosphinous acid 9 A" 375 244 -132 1.540
ZnCH3 Zinc monomethyl 6 E 315 592 277 0.532
CH3BO Borane, methyloxo- 7 E 897 1428 531 0.628