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 B3LYP/3-21G*
Calculated values were scaled by 0.962.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 163 50 0.692
C4H10O Ethoxy ethane 12 A1 240 177 -63 1.359
C4H10O Ethoxy ethane 20 A2 137 103 -34 1.324
C4H10O Ethoxy ethane 28 B1 126 93 -33 1.356
CH3CONH2 Acetamide 20 A 259 400 141 0.647
CH3OH Methyl alcohol 12 torsion A" 200 371 171 0.539
C2H4+ Ethylene cation 4 torsion Au 84 -502 -586 -0.168
CH2I2 Diiodomethane 3 A1 704 468 -236 1.505
CH2I2 Diiodomethane 4 A1 285 110 -175 2.599
CH2I2 Diiodomethane 7 B1 896 703 -193 1.274
CH2I2 Diiodomethane 9 B2 738 556 -182 1.328
CHONH2 formamide 12 torsion A" 289 479 190 0.603
HNCO Isocyanic acid 4 A' 777 574 -203 1.354
CH3SCH3+ dimethyl sulfide cation 15 B1 172 124 -48 1.388
C3F8 perfluoropropane 13 A2 276 202 -74 1.368
CH3COOCH3 methyl acetate 26 torsion A" 136 68 -68 2.009
CH3COOCH3 methyl acetate 27 torsion A" 110 60 -50 1.846
CH3CH2CH2CH3 Butane 5 Ag 1442 414 -1028 3.486
CH3CH2CH2CH3 Butane 7 Ag 1361 809 -552 1.683
CH3CH2CH2CH3 Butane 30 Bu 1461 2930 1469 0.499
CH3CH2CH2CH3 Butane 35 Bu 964 2992 2028 0.322
C3H6O 2-Propen-1-ol 22 A 377 300 -77 1.256
C3H6O 2-Propen-1-ol 24 A 188 101 -88 1.872
CH2ClCHO chloroacetaldehyde 15 torsion A 27 68 41 0.399
CH2ClCHO chloroacetaldehyde 15 A" 59 174 115 0.340
C2H2O2 Ethanedial 7 torsion Au 127 198 71 0.643
CH3OCHO methyl formate 18 torsion A" 130 58 -72 2.239
C3F6 hexafluoropropene 21 A" 60 25 -35 2.440
C4H9N Pyrrolidine 36 A" 65 34 -31 1.908
C4H8O2 1,4-Dioxane 19 Au 288 218 -70 1.320
C5H8 Cyclopentene 18 torsion A' 254 115 -139 2.207
C4H8 cyclobutane 6 torsion A1 199 155 -44 1.283
CH2N4 1H-Tetrazole 11 A' 925 735 -190 1.259
C2H2N4 sym-tetrazine 13 B2u 883 699 -184 1.264
N2H4 Hydrazine 6 A 780 619 -161 1.259
C4H6O2 2,3-Butanedione 16 torsion Au 48 17 -31 2.863
C4H6O2 2,3-Butanedione 21 torsion Bg 240 48 -192 4.955
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 981 -410 1.418
C2N2 Cyanogen 4 Πg 503 760 257 0.662
C5H12 Propane, 2,2-dimethyl- 12 T1 203 315 112 0.645
C2H3NO3 Oxamic acid 3 A' 2600 3343 743 0.778
C2H3NO3 Oxamic acid 15 A' 328 256 -72 1.280
C2H3NO3 Oxamic acid 21 A" 162 114 -48 1.422
C3H6O Oxetane 23 B2 1228 934 -294 1.314
C3O2 Carbon suboxide 7 Πu 61 147 86 0.415
HCNO fulminic acid 5 torsion Π 224 525 301 0.427
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 685 -2394 4.497
C5H8 1,4-Pentadiene 16 A 137 301 164 0.455
C5H8 1,4-Pentadiene 17 torsion A 102 81 -21 1.259
C5H8 1,4-Pentadiene 17 torsion A 102 81 -21 1.259
P(CH3)3 trimethylphosphine 22 E 259 200 -59 1.297
C2H4F2 1,2-difluoroethane 18 Bu 295 224 -71 1.317
C6H6 Benzvalene 10 A1 996 775 -221 1.286
H2CS- thioformaldehyde anion 4 B1 450 206 -244 2.187
C4N2 2-Butynedinitrile 6 Πg 504 909 405 0.554
C4N2 2-Butynedinitrile 8 Πu 472 687 215 0.687
LiOH lithium hydroxide 3 Π 257 408 151 0.629
SiF2+ Silicon difluoride cation 2 A1 350 273 -77 1.282
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 220 76 0.654
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 346 -110 1.319
CCl2 dichloromethylene 3 B2 758 576 -181 1.315
CFCl2 dichlorofluoromethyl radical 2 A' 747 519 -228 1.440
FCO+ Carbonyl fluoride cation 3 Π 650 493 -157 1.318
CH3OO methylperoxy radical 12 torsion A" 170 129 -41 1.318
CH3 Methyl radical 2 torsion A2" 606 474 -132 1.278
CH2OH Hydroxymethyl radical 9 torsion A 234 416 182 0.563
ClCO carbonyl monochloride 3 A' 335 218 -116 1.534
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 863 -273 1.316
C6H8 (Z)-hexa-1,3,5-triene 19 torsion A2 264 147 -117 1.792
C6H8 (Z)-hexa-1,3,5-triene 24 torsion B1 358 98 -260 3.655
C6H8 (Z)-hexa-1,3,5-triene 36 B2 243 350 107 0.694
HCCN cyanomethylene 4 Π 383 593 210 0.646
HCCN cyanomethylene 5 Π 129 375 246 0.344
HNCS Isothiocyanic acid 5 A' 469 224 -246 2.098
CH3SO2NH2 methanesulfonamide 11 A' 689 490 -199 1.406
CH3SO2NH2 methanesulfonamide 13 A' 493 392 -101 1.257
CHCl2 dichloromethyl radical 4 A' 190 288 98 0.661
NF2 Difluoroamino radical 2 A1 573 453 -120 1.266
CH2Cl chloromethyl radical 4 B1 402 233 -169 1.726
TeO2 Tellurium Dioxide 1 A1 823 243 -580 3.387
C2Cl2 dichloroacetylene 4 Πg 333 488 155 0.683
HClO4 perchloric acid 12 A" 191 85 -106 2.236
BF3+ boron trifluoride cation 5 B2 1791 738 -1053 2.427
NH3 Ammonia 2 torsion A1 950 736 -214 1.290
H2SO4 Sulfuric acid 8 A 224 154 -70 1.450
H2SO4 Sulfuric acid 15 torsion B 288 217 -70 1.324
H2SO4 Sulfuric acid 15 torsion B 288 217 -70 1.324
H2O2 Hydrogen peroxide 4 torsion A 371 76 -295 4.895
O2+ diatomic oxygen cation 1 Σg 1873 1408 -465 1.331
HN3+ Hydrazoic acid cation 4 A' 850 557 -293 1.526
FOOF Perfluoroperoxide 1 A 1210 935 -275 1.294
FOOF Perfluoroperoxide 4 torsion A 202 162 -40 1.248
FOOF Perfluoroperoxide 5 B 614 908 294 0.676
NF3 Nitrogen trifluoride 4 E 492 383 -109 1.286
BeBr2 Beryllium bromide 3 Πu 207 344 137 0.601
BeF2 Beryllium fluoride 3 Πu 343 259 -83 1.321
CaBr2 Calcium dibromide 3 Πu 72 133 61 0.543
ClF3 Chlorine trifluoride 6 B2 442 342 -100 1.292
ClSSCl Disulfur dichloride 5 B 461 368 -93 1.253
O3 Ozone 2 A1 705 550 -155 1.281
OClO- Chlorine dioxide anion 1 A1 790 606 -184 1.303
OClO- Chlorine dioxide anion 2 A1 418 322 -96 1.300
NO2 Nitrogen dioxide 3 B2 1618 1278 -340 1.266
BCl3+ Boron Trichloride cation 3 E' 1104 773 -331 1.428
NHF2 difluoramine 4 A' 500 401 -99 1.248
S8 Octasulfur 3 B1 411 324 -87 1.267
N2O4 Dinitrogen tetroxide 9 B2u 265 183 -82 1.450
N2O3 Dinitrogen trioxide 9 torsion A" 63 150 87 0.420
SF5 Sulfur pentafluoride 9 E 387 306 -81 1.267
C3O Tricarbon monoxide 5 Π 109 195 86 0.558
AsSe Arsenic monoselenide 1 Σ 280 405 125 0.692
Li2O dilithium oxide 3 Πu 112 71 -41 1.570
SiC2 Silicon dicarbide 3 B2 196 157 -39 1.252
C3 carbon trimer 3 Πu 63 158 94 0.403
S3 Sulfur trimer 2 A1 281 566 285 0.496
NI3 Nitrogen triiodide 3 E 354 513 159 0.691
ND3 Ammonia-d3 2 A1 748 561 -187 1.333
XeF4 Xenon tetrafluoride 5 B2u 216 166 -50 1.302
NH2- amino anion 1 A1 3122 2528 -594 1.235
NH2- amino anion 3 B2 3190 2556 -634 1.248
SiH2D2 silane-d2 6 B1 2183 1589 -594 1.373
SiH2D2 silane-d2 8 B2 1601 2199 598 0.728
H3O+ hydronium cation 2 A1 954 460 -494 2.073
C2H4O4 Formic acid dimer 2 Ag 2949 2134 -815 1.382
C2H4O4 Formic acid dimer 18 Bu 2939 2391 -548 1.229
C2H4O4 Formic acid dimer 24 Bu 268 407 139 0.659
ClONO2 Chlorine nitrate 7 A' 273 218 -56 1.256
NH4 Ammonium radical 2 E 1581 1261 -320 1.254
FOO Dioxygen monofluoride radical 1 A' 1487 1084 -403 1.372
ClOO chloroperoxy radical 1 A' 1443 1084 -359 1.331
B4H10 Tetraborane(10) 11 A1 785 550 -235 1.427
B4H10 Tetraborane(10) 12 A1 559 234 -325 2.388
B4H10 Tetraborane(10) 19 A2 662 398 -264 1.664
B4H10 Tetraborane(10) 36 B2 236 369 133 0.639
AlCN Aluminum monocyanide 3 Π 132 290 158 0.455
B5H9 pentaborane9 13 B1 240 611 371 0.393
B5H9 pentaborane9 16 B2 1036 782 -254 1.325
B5H9 pentaborane9 18 B2 600 443 -157 1.354
B5H9 pentaborane9 22 E 1409 1076 -333 1.309
CaS Calcium sulfide 1 Σ 459 367 -92 1.249
OPCl Phosphorus oxychloride 2 A' 308 451 143 0.682
OPCl Phosphorus oxychloride 3 A' 492 282 -210 1.745
S2N2 Disulfur dinitride 4 B2u 790 631 -159 1.252
H2OH2O water dimer 6 A' 311 539 228 0.577
H2OH2O water dimer 7 A' 143 288 145 0.496
H2OH2O water dimer 8 A' 103 197 94 0.523
H2OH2O water dimer 10 A" 523 857 334 0.610
H2OH2O water dimer 11 A" 108 221 113 0.489
Na2 Sodium diatomic 1 Σg 158 267 110 0.590
H2POH Phosphinous acid 9 A" 375 211 -164 1.780
Mg2 Magnesium diatomic 1 Σg 48 87 39 0.553
CHFCl Chlorofluoromethyl radical 6 A 540 365 -175 1.479
C5H6 Propellane 9 A2" 615 470 -145 1.308
ClS2 Sulfur chloride 2 A' 450 352 -98 1.278
ZnCH3 Zinc monomethyl 6 E 315 634 319 0.497
H2CNCN cyanamide, methylene 3 A' 2208 2963 755 0.745
H2CNCN cyanamide, methylene 4 A' 1621 2185 564 0.742
C2H3NO Nitrosoethylene 11 A' 490 321 -169 1.528
SNO Nitrogen oxide sulfide 3 A' 792 448 -344 1.767
ONNO NO dimer 2 A1 239 466 227 0.513
ONNO NO dimer 3 A1 135 301 166 0.447
ONNO NO dimer 4 torsion A2 117 223 106 0.524
ONNO NO dimer 5 B2 1789 1394 -395 1.283
ONNO NO dimer 6 B2 429 680 250 0.632
INO Nitrosyl iodide 2 A' 216 504 288 0.429
INO Nitrosyl iodide 3 A' 470 254 -216 1.853
AlNC Aluminum isocyanide 3 Π 100 165 65 0.605
ClONO chlorine nitrite 5 A' 270 213 -57 1.270
BrOO Bromine dioxide 1 A' 1487 1048 -439 1.420
HSO3 Hydroxysulfonyl radical 3 A 1296 1035 -261 1.253
ONONO Nitrosyl nitrite 6 B1 140 111 -29 1.258
ONONO Nitrosyl nitrite 9 B2 380 586 206 0.649