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 PBE1PBE/3-21G
Calculated values were scaled by 0.9604.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 370 170 0.541
CH2I2 Diiodomethane 3 A1 704 489 -215 1.438
CH2I2 Diiodomethane 4 A1 285 112 -173 2.542
CH2I2 Diiodomethane 7 B1 896 710 -186 1.262
CHONH2 formamide 12 torsion A" 289 502 213 0.576
CH3SCH3+ dimethyl sulfide cation 15 B1 172 132 -40 1.306
CH3CH2CH2CH3 Butane 5 Ag 1442 419 -1023 3.444
CH3CH2CH2CH3 Butane 8 Ag 1151 823 -328 1.399
CH3CH2CH2CH3 Butane 30 Bu 1461 2943 1482 0.496
CH3CH2CH2CH3 Butane 35 Bu 964 3015 2051 0.320
C3H6O 2-Propen-1-ol 22 A 377 299 -78 1.261
C3H6O 2-Propen-1-ol 24 A 188 100 -88 1.883
C2H2O2 Ethanedial 7 torsion Au 127 197 70 0.645
C3F6 hexafluoropropene 21 A" 60 18 -42 3.369
N2H4 Hydrazine 6 A 780 608 -172 1.282
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 1006 -385 1.383
C2N2 Cyanogen 4 Πg 503 764 261 0.658
C3H6O Oxetane 23 B2 1228 967 -261 1.270
C3O2 Carbon suboxide 7 Πu 61 147 86 0.415
HCNO fulminic acid 5 torsion Π 224 535 311 0.419
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 693 -2386 4.443
C2H4F2 1,2-difluoroethane 18 Bu 295 224 -71 1.318
C6H6 Benzvalene 10 A1 996 785 -211 1.268
H2CS- thioformaldehyde anion 4 B1 450 261 -189 1.722
CH2ClCCCl 1,3-dichloropropyne 14 A" 337 482 145 0.700
LiOH lithium hydroxide 3 Π 257 407 150 0.631
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 222 78 0.648
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 345 -111 1.323
CFCl2 dichlorofluoromethyl radical 2 A' 747 542 -205 1.377
FCO+ Carbonyl fluoride cation 3 Π 650 503 -147 1.292
C2H Ethynyl radical 3 torsion Π 372 551 179 0.675
CH3 Methyl radical 2 torsion A2" 606 474 -132 1.278
CH2OH Hydroxymethyl radical 9 torsion A 234 406 172 0.576
HCCN cyanomethylene 4 Π 383 591 208 0.648
HCCN cyanomethylene 5 Π 129 365 236 0.353
CH2Cl chloromethyl radical 4 B1 402 284 -118 1.418
BF3+ boron trifluoride cation 5 B2 1791 704 -1087 2.545
NH3 Ammonia 2 torsion A1 950 702 -248 1.354
H2O2 Hydrogen peroxide 4 torsion A 371 70 -301 5.321
O2+ diatomic oxygen cation 1 Σg 1873 1457 -416 1.285
HN3+ Hydrazoic acid cation 4 A' 850 623 -227 1.365
BeBr2 Beryllium bromide 3 Πu 207 342 135 0.606
BeF2 Beryllium fluoride 3 Πu 343 258 -85 1.330
CaBr2 Calcium dibromide 3 Πu 72 135 63 0.533
BCl3+ Boron Trichloride cation 3 E' 1104 784 -320 1.409
C3O Tricarbon monoxide 5 Π 109 194 85 0.562
Li2O dilithium oxide 3 Πu 112 74 -37 1.505
C3 carbon trimer 3 Πu 63 158 94 0.402
S3 Sulfur trimer 2 A1 281 596 315 0.471
NI3 Nitrogen triiodide 3 E 354 564 210 0.627
XeF4 Xenon tetrafluoride 5 B2u 216 172 -44 1.254
SiH2D2 silane-d2 6 B1 2183 1587 -596 1.376
SiH2D2 silane-d2 8 B2 1601 2195 594 0.729
H3O+ hydronium cation 2 A1 954 474 -480 2.012
C2H4O4 Formic acid dimer 2 Ag 2949 1998 -951 1.476
C2H4O4 Formic acid dimer 18 Bu 2939 2273 -665 1.293
C2H4O4 Formic acid dimer 24 Bu 268 446 178 0.602
NH4 Ammonium radical 2 E 1581 1251 -330 1.264
B4H10 Tetraborane(10) 11 A1 785 586 -199 1.339
B4H10 Tetraborane(10) 12 A1 559 244 -315 2.295
B4H10 Tetraborane(10) 19 A2 662 398 -264 1.662
B4H10 Tetraborane(10) 36 B2 236 374 138 0.632
AlCN Aluminum monocyanide 3 Π 132 288 156 0.458
B5H9 pentaborane9 13 B1 240 610 370 0.393
B5H9 pentaborane9 16 B2 1036 783 -253 1.323
B5H9 pentaborane9 18 B2 600 466 -134 1.287
B5H9 pentaborane9 22 E 1409 1062 -347 1.326
OPCl Phosphorus oxychloride 2 A' 308 478 170 0.644
OPCl Phosphorus oxychloride 3 A' 492 293 -199 1.681
H2OH2O water dimer 6 A' 311 554 243 0.561
H2OH2O water dimer 7 A' 143 297 154 0.481
H2OH2O water dimer 8 A' 103 201 98 0.512
H2OH2O water dimer 10 A" 523 887 364 0.590
H2OH2O water dimer 11 A" 108 222 114 0.486
Na2 Sodium diatomic 1 Σg 158 251 93 0.629
CHFCl Chlorofluoromethyl radical 6 A 540 373 -167 1.446
H2CNCN cyanamide, methylene 3 A' 2208 2978 770 0.741
H2CNCN cyanamide, methylene 4 A' 1621 2211 590 0.733
C2H3NO Nitrosoethylene 11 A' 490 319 -171 1.534
SNO Nitrogen oxide sulfide 3 A' 792 456 -336 1.738
ONNO NO dimer 2 A1 239 489 250 0.489
ONNO NO dimer 3 A1 135 313 179 0.429
ONNO NO dimer 4 torsion A2 117 224 107 0.521
ONNO NO dimer 5 B2 1789 1428 -361 1.252
ONNO NO dimer 6 B2 429 706 277 0.607
AlNC Aluminum isocyanide 3 Π 100 166 66 0.601
BrOO Bromine dioxide 1 A' 1487 1045 -442 1.422
ONONO Nitrosyl nitrite 9 B2 380 611 231 0.622