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)/aug-cc-pVDZ
Calculated values were scaled by 0.9625.

Species Name mode Symmetry Experiment Theory difference ratio
CHONH2 formamide 12 A" 289 -45 -334 -6.426
C2H2 Acetylene 4 Πg 612 354 -258 1.728
C2H4+ Ethylene cation 4 Au 84 -268 -352 -0.314
CH3OH Methyl alcohol 12 A" 200 298 98 0.671
C3H6O Oxetane 18 B1 90 -79 -169 -1.139
C3H6O Oxetane 23 B2 1228 972 -256 1.264
HCCCl Chloroacetylene 5 Π 326 233 -93 1.398
CH2NN diazomethane 6 B1 406 288 -118 1.409
C4H2 Diacetylene 7 Πg 482 -637 -1119 -0.757
C4H2 Diacetylene 8 Πu 630 481 -149 1.310
C4H2 Diacetylene 9 Πu 231 110 -121 2.102
F2CCCF2 tetrafluoroallene 8 E 1248 565 -683 2.210
F2CCCF2 tetrafluoroallene 11 E 90 63 -27 1.420
C3H6O Oxetane 12 A2 986 789 -197 1.250
C6H6 Benzvalene 10 A1 996 724 -272 1.375
HCNO fulminic acid 5 Π 224 -236 -461 -0.948
H2CS- thioformaldehyde anion 4 B1 450 214 -236 2.100
SiF2+ Silicon difluoride cation 2 A1 350 272 -78 1.288
C2H- Ethynyl anion 3 Π 505 382 -123 1.321
C2H Ethynyl radical 3 Π 372 -152 -524 -2.438
CH2OH Hydroxymethyl radical 9 A 234 413 179 0.566
CHCl2 dichloromethyl radical 4 A' 190 289 99 0.659
HCCN cyanomethylene 5 Π 129 -481 -610 -0.268
CH3 Methyl radical 2 A2" 606 480 -127 1.265
SF5 Sulfur pentafluoride 7 E 818 585 -233 1.397
SiH- silicon monohydride anion 1 Σ 2175 1737 -438 1.252
OClO- Chlorine dioxide anion 2 A1 418 309 -109 1.353
SF5 Sulfur pentafluoride 2 A1 633 475 -158 1.332
SF5 Sulfur pentafluoride 9 E 387 307 -80 1.261
C3O Tricarbon monoxide 5 Π 109 -78 -187 -1.392
C3 carbon trimer 3 Πu 63 -167 -230 -0.380
N3 azide radical 3 Πu 457 755 298 0.605
F3- trifluoride anion 1 Σg 461 366 -95 1.260
H2POH Phosphinous acid 9 A" 375 246 -130 1.528
Mg2 Magnesium diatomic 1 Σg 51 24 -27 2.161
SF5Cl sulfur chloropentafluoride 11 E 273 886 613 0.308
Cl3- trichloride anion 2 Σu 327 257 -70 1.271
OPCl Phosphorus oxychloride 2 A' 308 458 150 0.673
OPCl Phosphorus oxychloride 3 A' 492 277 -215 1.778
H2OH2O water dimer 12 A" 88 126 38 0.698