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 0.9598.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 369 169 0.542
CH2I2 Diiodomethane 3 A1 704 489 -215 1.439
CH2I2 Diiodomethane 4 A1 285 112 -173 2.543
CH2I2 Diiodomethane 7 B1 896 710 -186 1.263
CHONH2 formamide 12 torsion A" 289 501 213 0.576
CH3SCH3+ dimethyl sulfide cation 15 B1 172 132 -40 1.307
CH3CH2CH2CH3 Butane 5 Ag 1442 418 -1024 3.446
CH3CH2CH2CH3 Butane 8 Ag 1151 822 -329 1.400
CH3CH2CH2CH3 Butane 30 Bu 1461 2941 1480 0.497
CH3CH2CH2CH3 Butane 35 Bu 964 3014 2050 0.320
C3H6O 2-Propen-1-ol 22 A 377 299 -78 1.262
C3H6O 2-Propen-1-ol 24 A 188 100 -88 1.884
C2H2O2 Ethanedial 7 torsion Au 127 197 70 0.645
C3F6 hexafluoropropene 21 A" 60 18 -42 3.372
N2H4 Hydrazine 6 A 780 608 -172 1.283
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 1005 -386 1.383
C2N2 Cyanogen 4 Πg 503 763 260 0.659
C3H6O Oxetane 23 B2 1228 966 -262 1.271
C3O2 Carbon suboxide 7 Πu 61 147 86 0.415
HCNO fulminic acid 5 torsion Π 224 534 310 0.419
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 692 -2386 4.446
C2H4F2 1,2-difluoroethane 18 Bu 295 224 -71 1.318
H2CS- thioformaldehyde anion 4 B1 450 261 -189 1.724
LiOH lithium hydroxide 3 Π 257 406 150 0.631
SiF2+ Silicon difluoride cation 2 A1 350 275 -75 1.273
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 222 78 0.648
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 344 -112 1.324
CFCl2 dichlorofluoromethyl radical 2 A' 747 542 -205 1.378
FCO+ Carbonyl fluoride cation 3 Π 650 503 -147 1.293
C2H Ethynyl radical 3 torsion Π 372 551 179 0.675
CH3 Methyl radical 2 torsion A2" 606 474 -132 1.279
CH2OH Hydroxymethyl radical 9 torsion A 234 406 172 0.577
HCCN cyanomethylene 4 Π 383 590 207 0.649
HCCN cyanomethylene 5 Π 129 365 236 0.354
CH3SO2NH2 methanesulfonamide 11 A' 689 506 -183 1.361
CH2Cl chloromethyl radical 4 B1 402 283 -119 1.419
C6H6 Benzvalene 10 A1 996 785 -211 1.269
P(CH3)3 trimethylphosphine 22 E 259 202 -57 1.284
HClO4 perchloric acid 12 A" 191 131 -60 1.460
BF3+ boron trifluoride cation 5 B2 1791 703 -1087 2.546
NH3 Ammonia 2 torsion A1 950 701 -249 1.355
H2O2 Hydrogen peroxide 4 torsion A 371 70 -301 5.324
O2+ diatomic oxygen cation 1 Σg 1873 1456 -417 1.286
HN3+ Hydrazoic acid cation 4 A' 850 622 -228 1.366
BeBr2 Beryllium bromide 3 Πu 207 341 134 0.606
BeF2 Beryllium fluoride 3 Πu 343 257 -85 1.331
CaBr2 Calcium dibromide 3 Πu 72 135 63 0.534
BCl3+ Boron Trichloride cation 3 E' 1104 783 -321 1.410
C3O Tricarbon monoxide 5 Π 109 194 85 0.562
AsSe Arsenic monoselenide 1 Σ 280 418 138 0.670
Li2O dilithium oxide 3 Πu 112 74 -37 1.506
C3 carbon trimer 3 Πu 63 157 94 0.403
S3 Sulfur trimer 2 A1 281 596 315 0.472
NI3 Nitrogen triiodide 3 E 354 564 210 0.628
XeF4 Xenon tetrafluoride 5 B2u 216 172 -44 1.255
SiH2D2 silane-d2 6 B1 2183 1586 -597 1.377
SiH2D2 silane-d2 8 B2 1601 2194 593 0.730
H3O+ hydronium cation 2 A1 954 474 -480 2.014
C2H4O4 Formic acid dimer 2 Ag 2949 1997 -952 1.477
C2H4O4 Formic acid dimer 18 Bu 2939 2272 -667 1.294
C2H4O4 Formic acid dimer 24 Bu 268 445 177 0.602
NH4 Ammonium radical 2 E 1581 1250 -331 1.265
AlCN Aluminum monocyanide 3 Π 132 288 156 0.458
OPCl Phosphorus oxychloride 2 A' 308 478 170 0.644
OPCl Phosphorus oxychloride 3 A' 492 292 -200 1.682
H2OH2O water dimer 6 A' 311 554 243 0.562
H2OH2O water dimer 7 A' 143 297 154 0.482
H2OH2O water dimer 8 A' 103 201 98 0.512
H2OH2O water dimer 10 A" 523 886 363 0.590
H2OH2O water dimer 11 A" 108 222 114 0.486
Na2 Sodium diatomic 1 Σg 158 250 93 0.630
H2POH Phosphinous acid 9 A" 375 224 -151 1.672
Mg2 Magnesium diatomic 1 Σg 48 118 70 0.407
CHFCl Chlorofluoromethyl radical 6 A 540 373 -167 1.447
H2CNCN cyanamide, methylene 3 A' 2208 2977 769 0.742
H2CNCN cyanamide, methylene 4 A' 1621 2209 588 0.734
C2H3NO Nitrosoethylene 11 A' 490 319 -171 1.535
SNO Nitrogen oxide sulfide 3 A' 792 456 -337 1.739
ONNO NO dimer 2 A1 239 489 249 0.490
ONNO NO dimer 3 A1 135 313 179 0.430
ONNO NO dimer 4 torsion A2 117 224 107 0.522
ONNO NO dimer 5 B2 1789 1428 -362 1.253
ONNO NO dimer 6 B2 429 706 277 0.608
INO Nitrosyl iodide 2 A' 216 519 303 0.417
INO Nitrosyl iodide 3 A' 470 266 -204 1.767
AlNC Aluminum isocyanide 3 Π 100 166 66 0.602
BrOO Bromine dioxide 1 A' 1487 1045 -442 1.423
ONONO Nitrosyl nitrite 9 B2 380 610 230 0.622
B5H9 pentaborane9 13 B1 240 610 370 0.394
B5H9 pentaborane9 16 B2 1036 783 -253 1.324
B5H9 pentaborane9 18 B2 600 466 -134 1.288
B5H9 pentaborane9 22 E 1409 1062 -347 1.327
B4H10 Tetraborane(10) 11 A1 785 586 -199 1.339
B4H10 Tetraborane(10) 12 A1 559 243 -316 2.296
B4H10 Tetraborane(10) 19 A2 662 398 -264 1.663
B4H10 Tetraborane(10) 36 B2 236 373 137 0.632