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 MP2/6-31G*
Calculated values were scaled by 0.943.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3SeH Methane selenol 12 torsion A" 145 211 66 0.688
C3H4O2 β–Propiolactone 21 A" 113 162 49 0.699
C4H10O Ethoxy ethane 12 A1 240 186 -54 1.288
C4H10O Ethoxy ethane 20 A2 137 93 -44 1.476
CH3OH Methyl alcohol 12 torsion A" 200 336 136 0.595
C2Cl6 hexachloroethane 4 A1u 61 87 26 0.698
C6H6 Benzene 8 B2g 703 477 -226 1.473
CH3CCl3 Ethane, 1,1,1-trichloro- 6 torsion A2 214 315 101 0.679
C2H4+ Ethylene cation 4 torsion Au 84 -65 -150 -1.285
C2H2 Acetylene 4 Πg 612 353 -259 1.733
HCN+ hydrogen cyanide cation 1 Σ 3050 3743 693 0.815
HCN+ hydrogen cyanide cation 2 Σ 1800 2790 990 0.645
CH3CCH propyne 9 E 633 486 -147 1.303
CH3CCH propyne 10 E 328 217 -111 1.511
CHONH2 formamide 12 torsion A" 289 -129 -418 -2.237
CH3SCH3+ dimethyl sulfide cation 15 B1 172 134 -38 1.283
C3F8 perfluoropropane 13 A2 276 211 -65 1.309
CHOCH(CH3)CH3 Propanal, 2-methyl- 33 A" 75 57 -18 1.319
CH3COCH2CH3 2-Butanone 33 torsion A" 87 35 -52 2.494
CH3COOCH3 methyl acetate 27 torsion A" 110 68 -42 1.624
C13H10 Fluorene 29 A2 566 364 -202 1.556
C10H8 naphthalene 12 Au 581 442 -139 1.314
C10H8 naphthalene 27 B2g 770 412 -358 1.869
C10H8 naphthalene 28 B2g 461 -161 -622 -2.862
C9H8 Indene 40 A" 690 503 -187 1.371
C9H8 Indene 41 A" 549 430 -118 1.275
C6H4Cl2 1,2-dichlorobenzene 14 A2 695 465 -230 1.495
C6H5NO2 Nitrobenzene 22 B1 675 470 -205 1.435
C6H5CHCH2 Styrene 38 A" 633 434 -199 1.458
C6H5CN phenyl cyanide 19 B1 688 519 -169 1.325
C6H5CHO benzaldehyde 32 A" 688 478 -210 1.440
C6H4Cl2 1,4-dichlorobenzene 16 B2g 687 444 -243 1.549
C6H4Cl2 1,4-dichlorobenzene 30 B3u 122 96 -26 1.273
C6H4O2 parabenzoquinone 17 B2g 241 170 -71 1.421
C6H4O2 parabenzoquinone 30 B3u 109 85 -23 1.276
CHCCH2CH3 1-Butyne 22 A" 630 493 -137 1.277
C3H6O 2-Propen-1-ol 24 A 188 108 -80 1.747
CH2ClCHO chloroacetaldehyde 15 A" 59 150 91 0.393
C6H5Cl chlorobenzene 18 B1 685 462 -222 1.480
CHSNH2 thioformamide 12 A" 393 255 -138 1.539
C3F6 hexafluoropropene 21 A" 60 32 -28 1.870
C5H8 Cyclopentene 18 torsion A' 254 173 -81 1.470
CH2NN diazomethane 6 B1 406 -104 -510 -3.911
C6F6 hexafluorobenzene 7 B2g 719 195 -524 3.681
C6F6 hexafluorobenzene 8 B2g 205 -222 -427 -0.924
NH2CN cyanamide 5 torsion A' 408 655 247 0.623
C4H6O2 2,3-Butanedione 21 torsion Bg 240 119 -121 2.009
C4H2 Diacetylene 7 Πg 482 227 -255 2.124
C4H2 Diacetylene 8 Πu 630 425 -205 1.481
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 1020 -371 1.364
F2CCCF2 tetrafluoroallene 11 E 90 66 -24 1.361
C6H5F Fluorobenzene 18 B1 685 491 -194 1.394
C2H3NO3 Oxamic acid 3 A' 2600 3423 823 0.760
C2H3NO3 Oxamic acid 16 A" 984 759 -225 1.297
C2H3NO3 Oxamic acid 21 A" 162 52 -110 3.097
CH3CCCH3 2-Butyne 16 E" 371 158 -213 2.341
C3H6O Oxetane 18 B1 90 -86 -176 -1.040
C3O2 Carbon suboxide 7 Πu 61 100 39 0.610
HCNO fulminic acid 5 torsion Π 224 -361 -585 -0.622
C6H4F2 1,4-difluorobenzene 16 B2g 692 478 -214 1.446
C6H4Cl2 1,3-dichlorobenzene 18 B1 672 446 -226 1.506
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 666 -2413 4.622
C5H8 1,4-Pentadiene 16 A 137 290 153 0.472
C5H8 1,4-Pentadiene 33 torsion B 331 93 -238 3.546
HCCCl Chloroacetylene 5 Π 326 147 -179 2.215
P(CH3)3 trimethylphosphine 22 E 259 197 -62 1.312
C6H8 1,4-Cyclohexadiene 19 B1u 108 79 -29 1.375
CO+ carbon monoxide cation 1 Σ 2184 2722 538 0.802
C6H6 Benzvalene 10 A1 996 740 -256 1.345
C2F2 difluoroacetylene 4 Πg 270 174 -96 1.555
C6H10 2-Hexyne 24 A' 272 185 -87 1.469
C6H10 2-Hexyne 25 A' 115 84 -31 1.364
C6H10 2-Hexyne 38 A" 392 239 -153 1.638
H2CS- thioformaldehyde anion 4 B1 450 -194 -644 -2.323
CH2ClCCCl 1,3-dichloropropyne 14 A" 337 166 -171 2.030
NaOH sodium hydroxide 3 torsion Π 300 120 -180 2.491
FCO+ Carbonyl fluoride cation 3 Π 650 508 -142 1.279
CH2NH+ Methanimine cation 4 A' 1370 1808 438 0.758
CN Cyano radical 1 Σ 2042 2699 657 0.757
C2H Ethynyl radical 2 Σ 1841 2343 502 0.786
C2H Ethynyl radical 3 torsion Π 372 771 400 0.482
C2H+ Ethynyl cation 3 Π 550 786 237 0.699
CH3OO methylperoxy radical 12 torsion A" 170 129 -41 1.320
CH3 Methyl radical 2 torsion A2" 606 380 -227 1.597
CH2OH Hydroxymethyl radical 8 torsion A 482 742 260 0.650
CH2OH Hydroxymethyl radical 9 torsion A 234 435 201 0.538
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 864 -272 1.315
C6H8 (Z)-hexa-1,3,5-triene 19 torsion A2 264 123 -141 2.144
C6H8 (Z)-hexa-1,3,5-triene 24 torsion B1 358 89 -269 4.017
C6H6 2,4-Hexadiyne 14 E' 353 143 -210 2.477
CHCl2 dichloromethyl radical 4 A' 190 302 112 0.629
CH2CHO Vinyloxy radical 10 A" 703 1016 313 0.692
C4H6 Methylenecyclopropane 17 B1 360 264 -96 1.365
CH2Cl chloromethyl radical 4 B1 402 -244 -646 -1.651
HNC+ hydrogen isocyanide cation 2 Σ 2195 2653 458 0.827
C2Cl2 dichloroacetylene 4 Πg 333 -58 -391 -5.753
C2Cl2+ dichloroacetylene cation 5 Πu 233 168 -65 1.387
BF3+ boron trifluoride cation 5 B2 1791 3718 1927 0.482
O2+ diatomic oxygen cation 1 Σg 1873 1266 -607 1.480
HN3+ Hydrazoic acid cation 2 A' 1850 3161 1311 0.585
BeBr2 Beryllium bromide 3 Πu 207 335 128 0.617
HOCl+ hypochlorous acid cation 3 A' 830 1250 420 0.664
O3 Ozone 3 B2 1042 2244 1202 0.464
NO Nitric oxide 1 Σ 1876 3690 1814 0.508
NO2 Nitrogen dioxide 3 B2 1618 2142 524 0.755
BCl3+ Boron Trichloride cation 3 E' 1104 1505 401 0.734
N2O4 Dinitrogen tetroxide 9 B2u 265 181 -84 1.461
N2O3 Dinitrogen trioxide 9 torsion A" 63 165 102 0.382
C3O Tricarbon monoxide 5 Π 109 167 58 0.654
AsSe Arsenic monoselenide 1 Σ 280 401 121 0.698
NaO2 Sodium superoxide 3 B2 333 7170 6837 0.046
VO Vanadium monoxide 1 Σ 1002 2092 1090 0.479
Li2O dilithium oxide 3 Πu 112 62 -50 1.811
FO Oxygen monofluoride 1 Σ 1033 1456 423 0.710
SiC2 Silicon dicarbide 3 B2 196 150 -46 1.310
C3 carbon trimer 3 Πu 63 166 102 0.383
LiO2 Lithium dioxide 3 B2 509 2353 1844 0.216
SiP Silicon monophosphide 1 Σ 611 1260 649 0.485
BH+ boron monohydride cation 1 Σ 2153 2566 413 0.839
SiH2D2 silane-d2 6 B1 2183 1592 -591 1.371
SiH2D2 silane-d2 8 B2 1601 2203 602 0.727
ZnH2 Zinc hydride 3 Πu 633 494 -139 1.281
PO Phosphorus monoxide 1 Σ 1220 3869 2649 0.315
AlO Aluminum monoxide 1 Σ 965 724 -241 1.333
SCN thiocyanato radical 1 Σ 1942 2414 472 0.804
ClOO chloroperoxy radical 2 A' 414 1030 616 0.402
ClOO chloroperoxy radical 3 A' 201 468 267 0.430
B4H10 Tetraborane(10) 11 A1 785 575 -210 1.364
B4H10 Tetraborane(10) 12 A1 559 226 -333 2.477
B4H10 Tetraborane(10) 19 A2 662 420 -242 1.578
B4H10 Tetraborane(10) 36 B2 236 369 133 0.639
B5H9 pentaborane9 13 B1 240 611 371 0.393
B5H9 pentaborane9 16 B2 1036 781 -255 1.327
B5H9 pentaborane9 22 E 1409 1075 -334 1.310
OPCl Phosphorus oxychloride 2 A' 308 478 170 0.644
OPCl Phosphorus oxychloride 3 A' 492 286 -206 1.721
NCO isocyanato radical 1 Σ 1921 2366 445 0.812
H2POH Phosphinous acid 9 A" 375 258 -117 1.455
AsN Arsenic mononitride 1 Σ 1058 823 -235 1.285
Mg2 Magnesium diatomic 1 Σg 48 21 -27 2.270
CHFCl Chlorofluoromethyl radical 6 A 540 389 -151 1.388
ZnCH3 Zinc monomethyl 6 E 315 605 290 0.520
H2CNCN cyanamide, methylene 3 A' 2208 2981 773 0.741
H2CNCN cyanamide, methylene 4 A' 1621 2063 442 0.786
SNO Nitrogen oxide sulfide 3 A' 792 521 -271 1.519
ZnCN Zinc monocyanide 3 Π 212 -37 -249 -5.769
ONONO Nitrosyl nitrite 9 B2 380 263 -117 1.442