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

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 163 50 0.692
CH3CONH2 Acetamide 20 A 259 400 141 0.647
CH3OH Methyl alcohol 12 A" 200 373 173 0.536
C2H4+ Ethylene cation 4 Au 84 -502 -586 -0.168
CHONH2 formamide 12 A" 289 479 190 0.603
HNCO Isocyanic acid 4 A' 777 574 -203 1.354
C3F8 perfluoropropane 13 A2 276 202 -74 1.368
CH3COOCH3 methyl acetate 26 A" 136 68 -68 2.009
CH3COOCH3 methyl acetate 27 A" 110 60 -50 1.846
C3H6O 2-Propen-1-ol 22 A 377 300 -77 1.256
C3H6O 2-Propen-1-ol 24 A 188 101 -88 1.872
C2H2O2 Ethanedial 7 Au 127 198 71 0.642
CH3OCHO methyl formate 18 A" 130 58 -72 2.239
C4H8S Thiophene, tetrahydro- 5 A 1464 2963 1499 0.494
C4H8S Thiophene, tetrahydro- 6 A 1441 2963 1522 0.486
C4H8S Thiophene, tetrahydro- 7 A 1321 2950 1629 0.448
C4H8S Thiophene, tetrahydro- 8 A 1276 2949 1673 0.433
C4H8S Thiophene, tetrahydro- 11 A 1023 1480 457 0.691
C4H8S Thiophene, tetrahydro- 12 A 888 1477 589 0.601
C4H8S Thiophene, tetrahydro- 13 A 829 1337 508 0.620
C4H8S Thiophene, tetrahydro- 14 A 822 1324 502 0.621
C4H8S Thiophene, tetrahydro- 15 A 678 1284 606 0.528
C4H8S Thiophene, tetrahydro- 16 A 472 1278 806 0.369
C4H8S Thiophene, tetrahydro- 17 A 290 1226 936 0.237
C4H9N Pyrrolidine 36 A" 65 34 -31 1.908
C4H8O2 1,4-Dioxane 19 Au 288 218 -70 1.320
C5H8 Cyclopentene 18 A' 254 115 -139 2.207
C4H8 cyclobutane 6 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 Au 48 17 -31 2.863
C4H6O2 2,3-Butanedione 21 Bg 240 48 -192 4.955
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 Π 224 525 301 0.427
C5H8 1,4-Pentadiene 16 A 137 301 164 0.455
C5H8 1,4-Pentadiene 17 A 102 81 -21 1.259
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
FCO+ Carbonyl fluoride cation 3 Π 650 493 -157 1.318
CH3OO methylperoxy radical 12 A" 170 129 -41 1.318
CH3 Methyl radical 2 A2" 606 474 -132 1.278
CH2OH Hydroxymethyl radical 9 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 A2 264 147 -117 1.792
C6H8 (Z)-hexa-1,3,5-triene 24 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
OH- hydroxide anion 1 Σ 3738 2588 -1151 1.445
OH Hydroxyl radical 1 Σ 3738 3128 -609 1.195
CHCl2 dichloromethyl radical 4 A' 190 288 98 0.661
NF2 Difluoroamino radical 2 A1 573 453 -120 1.266
C2Cl2 dichloroacetylene 4 Πg 333 488 155 0.683
HClO4 perchloric acid 12 A" 191 85 -106 2.236
HF Hydrogen fluoride 1 Σ 4138 3490 -648 1.186
NH3 Ammonia 2 A1 950 735 -215 1.293
H2SO4 Sulfuric acid 8 A 224 154 -70 1.450
H2SO4 Sulfuric acid 15 B 288 217 -70 1.324
H2O2 Hydrogen peroxide 4 A 371 60 -311 6.180
O2+ diatomic oxygen cation 1 Σg 1906 1408 -498 1.354
FOOF Perfluoroperoxide 1 A 1210 935 -275 1.294
FOOF Perfluoroperoxide 4 A 202 162 -40 1.248
FOOF Perfluoroperoxide 5 B 614 908 294 0.676
NF3 Nitrogen trifluoride 4 E 492 384 -108 1.282
BeF2 Beryllium fluoride 3 Πu 343 259 -83 1.321
ClF3 Chlorine trifluoride 6 B2 442 342 -100 1.292
S2Cl2 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 1277 -341 1.267
S8 Octasulfur 3 B1 411 324 -87 1.267
N2O4 Dinitrogen tetroxide 9 B2u 265 180 -85 1.472
N2O3 Dinitrogen trioxide 9 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
NaK Sodium Potassium 1 Σ 124 92 -32 1.351
Li2O dilithium oxide 3 Πu 112 71 -41 1.570
C3 carbon trimer 3 Πu 63 157 93 0.405
BrNO Nitrosyl bromide 1 A' 1832 1464 -369 1.252
ND3 Ammonia-d3 2 A1 748 561 -187 1.333
NH2- amino anion 1 A1 3122 2528 -594 1.235
NH2- amino anion 3 B2 3190 2556 -634 1.248
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
FO2 Dioxygen monofluoride 1 A' 1487 1084 -403 1.372
ClOO chloroperoxy radical 1 A' 1443 1084 -359 1.331
CaS Calcium sulfide 1 Σ 462 367 -95 1.259
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 159 267 108 0.596
Mg2 Magnesium diatomic 1 Σg 51 87 35 0.590
ClS2 Sulfur chloride 2 A' 450 352 -98 1.278
INO Nitrosyl iodide 2 A' 216 504 288 0.429
INO Nitrosyl iodide 3 A' 470 254 -216 1.853
ClONO chlorine nitrite 5 A' 270 213 -57 1.270
ZnCH3 Zinc monomethyl 6 E 315 634 319 0.497
H2POH Phosphinous acid 9 A" 375 211 -164 1.780
S2N2 Disulfur dinitride 4 B2u 790 631 -159 1.252
OPCl Phosphorus oxychloride 3 A' 492 282 -210 1.745
OPCl Phosphorus oxychloride 2 A' 308 451 143 0.682
ONONO Nitrosyl nitrite 9 B2 380 586 206 0.649
ONONO Nitrosyl nitrite 6 B1 140 111 -29 1.258
HSO3 HOSO2 3 A 1296 1035 -261 1.253