return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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Bad vibrational frequency predictions

19 02 11 15 45

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 wB97X-D/CEP-31G*
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 347 147 0.576
CH3CHO+ acetaldehyde cation 15 A" 145 97 -48 1.491
C6H4Cl2 1,4-dichlorobenzene 30 B3u 122 101 -21 1.204
CH3CH2CH2CH3 Butane 5 Ag 1442 426 -1016 3.383
CH3CH2CH2CH3 Butane 8 Ag 1151 853 -298 1.350
CH3CH2CH2CH3 Butane 25 Bg 803 1512 709 0.531
CH3CH2CH2CH3 Butane 35 Bu 964 3143 2179 0.307
CHSNH2 thioformamide 12 A" 393 321 -72 1.225
C3F6 hexafluoropropene 21 A" 60 26 -34 2.322
CF3CHF2 pentafluoroethane 18 torsion A" 75 56 -19 1.350
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 1052 -339 1.322
CH2FCH2CH3 1-Fluoropropane 22 A" 890 1278 388 0.696
F2CCCF2 tetrafluoroallene 11 E 90 67 -23 1.353
C3O2 Carbon suboxide 7 Πu 61 184 123 0.331
C6H6 Benzvalene 10 A1 996 769 -227 1.295
H2CS- thioformaldehyde anion 4 B1 450 161 -289 2.801
SiF2+ Silicon difluoride cation 2 A1 350 281 -69 1.245
CFCl2 dichlorofluoromethyl radical 2 A' 747 613 -134 1.218
C2H5 Ethyl radical 9 A' 528 431 -97 1.224
CHCl2 dichloromethyl radical 4 A' 190 300 110 0.632
CH2Cl chloromethyl radical 4 B1 402 91 -311 4.395
HeH+ Helium hydride cation 1 Σ 2911 4939 2028 0.589
OClO- Chlorine dioxide anion 2 A1 418 334 -84 1.250
BCl3+ Boron Trichloride cation 3 E' 1104 775 -329 1.424
C3O Tricarbon monoxide 5 Π 109 244 135 0.447
SiC2 Silicon dicarbide 3 B2 196 -111 -308 -1.767
C3 carbon trimer 3 Πu 63 291 228 0.218
C4 Carbon tetramer 4 Πg 323 491 168 0.658
S3 Sulfur trimer 2 A1 281 632 351 0.445
SiH2D2 silane-d2 6 B1 2183 1630 -553 1.339
SiH2D2 silane-d2 8 B2 1601 2255 654 0.710
NH4 Ammonium radical 2 E 1581 1316 -265 1.201
BH3PH3 borane phosphine 12 E 447 362 -85 1.236
B5H9 pentaborane9 13 B1 240 615 375 0.390
B5H9 pentaborane9 16 B2 1036 789 -247 1.312
B5H9 pentaborane9 18 B2 600 484 -116 1.238
B5H9 pentaborane9 22 E 1409 1080 -329 1.305
OPCl Phosphorus oxychloride 2 A' 308 499 191 0.618
OPCl Phosphorus oxychloride 3 A' 492 307 -185 1.604
H2NN Isodiazene 5 B2 2805 3251 447 0.863
CHFCl Chlorofluoromethyl radical 6 A 540 406 -134 1.332
NH2NN+ hydrazoic acid, protonated 6 A' 489 270 -219 1.809
H2CNCN cyanamide, methylene 3 A' 2208 3129 921 0.706
H2CNCN cyanamide, methylene 4 A' 1621 2340 719 0.693
C2H3NO Nitrosoethylene 11 A' 490 341 -149 1.436
SNO Nitrogen oxide sulfide 3 A' 792 497 -295 1.594
ONNO NO dimer 2 A1 239 429 190 0.557
ONNO NO dimer 3 A1 135 332 197 0.405
ONNO NO dimer 4 torsion A2 117 184 67 0.637
ONNO NO dimer 6 B2 429 766 337 0.560
AlNC Aluminum isocyanide 3 Π 100 -43 -143 -2.334
ClONO chlorine nitrite 4 A' 406 592 186 0.686