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 QCISD/3-21G*
Calculated values were scaled by 0.9611.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 363 163 0.551
C2H4+ Ethylene cation 4 torsion Au 84 -347 -432 -0.242
CH2I2 Diiodomethane 3 A1 704 471 -233 1.494
CH2I2 Diiodomethane 4 A1 285 112 -173 2.547
CH2I2 Diiodomethane 7 B1 896 717 -179 1.250
CH2I2 Diiodomethane 9 B2 738 577 -161 1.279
HNCO Isocyanic acid 4 A' 777 594 -183 1.308
CH3SCH3+ dimethyl sulfide cation 15 B1 172 133 -39 1.293
C3F8 perfluoropropane 13 A2 276 202 -74 1.364
CH3COOCH3 methyl acetate 26 torsion A" 136 101 -35 1.352
C10H8 naphthalene 27 B2g 770 609 -161 1.264
CH3CH2CH2CH3 Butane 5 Ag 1442 413 -1029 3.489
CH3CH2CH2CH3 Butane 7 Ag 1361 799 -562 1.703
CH3CH2CH2CH3 Butane 30 Bu 1461 2904 1443 0.503
CH3CH2CH2CH3 Butane 35 Bu 964 2965 2001 0.325
CH2BrCH2Cl 1-bromo-2-chloroethane 1 A' 2960 190 -2770 15.543
CH2BrCH2Cl 1-bromo-2-chloroethane 2 A' 2960 243 -2717 12.168
CH2BrCH2Cl 1-bromo-2-chloroethane 3 A' 1446 636 -810 2.275
CH2BrCH2Cl 1-bromo-2-chloroethane 4 A' 1444 703 -741 2.053
CH2BrCH2Cl 1-bromo-2-chloroethane 5 A' 1284 977 -307 1.314
CH2BrCH2Cl 1-bromo-2-chloroethane 8 A' 726 1493 767 0.486
CH2BrCH2Cl 1-bromo-2-chloroethane 9 A' 630 1498 868 0.421
CH2BrCH2Cl 1-bromo-2-chloroethane 10 A' 251 2984 2733 0.084
CH2BrCH2Cl 1-bromo-2-chloroethane 11 A' 202 2992 2790 0.068
CH2BrCH2Cl 1-bromo-2-chloroethane 12 A" 3010 108 -2902 27.762
CH2BrCH2Cl 1-bromo-2-chloroethane 13 A" 3010 761 -2249 3.955
CH2BrCH2Cl 1-bromo-2-chloroethane 14 A" 1259 964 -295 1.305
CH2BrCH2Cl 1-bromo-2-chloroethane 17 A" 763 3038 2275 0.251
CH2BrCH2Cl 1-bromo-2-chloroethane 18 A" 123 3059 2936 0.040
C3H6O 2-Propen-1-ol 22 A 377 299 -78 1.261
C3H6O 2-Propen-1-ol 24 A 188 89 -99 2.108
CH2ClCHO chloroacetaldehyde 15 torsion A 27 66 39 0.408
CH2ClCHO chloroacetaldehyde 15 A" 59 161 102 0.366
C2H2O2 Ethanedial 7 torsion Au 127 188 61 0.674
C3F6 hexafluoropropene 21 A" 60 -11 -71 -5.290
C5H8 Cyclopentene 18 torsion A' 254 115 -139 2.201
CH2N4 1H-Tetrazole 11 A' 925 697 -228 1.328
C2H2N4 sym-tetrazine 13 B2u 883 411 -472 2.148
C4H6O2 2,3-Butanedione 16 torsion Au 48 72 24 0.670
C4H6O2 2,3-Butanedione 21 torsion Bg 240 97 -143 2.487
C4H2 Diacetylene 7 Πg 482 -636 -1118 -0.758
C4H2 Diacetylene 9 Πu 231 128 -103 1.799
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 970 -421 1.434
C2H3NO3 Oxamic acid 3 A' 2600 3363 763 0.773
C2H3NO3 Oxamic acid 15 A' 328 258 -70 1.272
C2H3NO3 Oxamic acid 17 A" 815 628 -187 1.298
C2H3NO3 Oxamic acid 21 A" 162 106 -56 1.526
C3H6O Oxetane 7 A1 1018 803 -215 1.268
C3H6O Oxetane 18 B1 90 67 -23 1.344
C3H6O Oxetane 23 B2 1228 921 -307 1.333
HCNO fulminic acid 3 Σ 1254 922 -332 1.360
HCNO fulminic acid 5 torsion Π 224 454 230 0.493
Zn(CH3)2 dimethyl zinc 11 E' 134 -95 -229 -1.414
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 683 -2396 4.508
C5H8 1,4-Pentadiene 16 A 137 295 158 0.465
C5H8 1,4-Pentadiene 17 torsion A 102 78 -24 1.306
C5H8 1,4-Pentadiene 17 torsion A 102 78 -24 1.306
P(CH3)3 trimethylphosphine 22 E 259 203 -56 1.277
C2H4F2 1,2-difluoroethane 18 Bu 295 226 -69 1.303
C6H8 1,4-Cyclohexadiene 19 B1u 108 80 -28 1.351
C6H6 Benzvalene 10 A1 996 793 -203 1.256
H2CS- thioformaldehyde anion 4 B1 450 175 -275 2.575
LiOH lithium hydroxide 3 Π 257 449 192 0.572
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 223 79 0.645
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 335 -121 1.361
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 111 -60 1.547
CCl2 dichloromethylene 3 B2 758 591 -167 1.282
CFCl2 dichlorofluoromethyl radical 2 A' 747 551 -196 1.356
FCO+ Carbonyl fluoride cation 3 Π 650 453 -197 1.434
CH3 Methyl radical 2 torsion A2" 606 481 -125 1.260
CH2OH Hydroxymethyl radical 9 torsion A 234 419 185 0.558
HCCN cyanomethylene 5 Π 129 -299 -428 -0.431
ClNO Nitrosyl chloride 1 A' 1800 1311 -488 1.373
H2CCCCH2 Butatriene 10 B2g 544 297 -247 1.830
H2CCCCH2 Butatriene 16 B3g 330 259 -71 1.274
HNCS Isothiocyanic acid 4 A' 615 463 -152 1.328
HNCS Isothiocyanic acid 5 A' 469 185 -284 2.534
CH3SO2NH2 methanesulfonamide 11 A' 689 511 -178 1.348
CHCl2 dichloromethyl radical 4 A' 190 293 103 0.648
CH2Cl chloromethyl radical 4 B1 402 68 -334 5.910
TeO2 Tellurium Dioxide 1 A1 823 229 -594 3.591
HClO4 perchloric acid 12 A" 191 28 -163 6.884
BF3+ boron trifluoride cation 5 B2 1791 391 -1400 4.580
HNO3 Nitric acid 4 A' 1325 1055 -270 1.256
HNO3 Nitric acid 7 A' 579 462 -117 1.254
HNO3 Nitric acid 8 A" 762 609 -153 1.252
H2O2 Hydrogen peroxide 4 torsion A 371 121 -250 3.073
O2+ diatomic oxygen cation 1 Σg 1873 1210 -663 1.548
HNO2 Nitrous acid 2 A' 1700 1350 -350 1.259
HN3 hydrogen azide 4 A' 1151 921 -230 1.249
HN3+ Hydrazoic acid cation 4 A' 850 488 -362 1.741
FOOF Perfluoroperoxide 1 A 1210 847 -363 1.428
FOOF Perfluoroperoxide 4 torsion A 202 135 -67 1.493
NF3 Nitrogen trifluoride 1 A1 1032 507 -525 2.035
NF3 Nitrogen trifluoride 3 E 907 380 -527 2.388
NF3 Nitrogen trifluoride 4 E 492 870 378 0.566
BeBr2 Beryllium bromide 3 Πu 207 333 126 0.622
BeF2 Beryllium fluoride 3 Πu 343 259 -83 1.321
FNO Nitrosyl fluoride 1 A' 1844 1330 -514 1.387
CaBr2 Calcium dibromide 3 Πu 72 119 47 0.606
N2O Nitrous oxide 2 Σ 1285 933 -352 1.377
N2O Nitrous oxide 3 Π 589 439 -150 1.340
O3 Ozone 2 A1 705 487 -218 1.449
O3 Ozone 3 B2 1042 -1196 -2238 -0.871
OClO- Chlorine dioxide anion 1 A1 790 550 -240 1.435
OClO- Chlorine dioxide anion 2 A1 418 291 -127 1.436
OClO Chlorine dioxide 1 A1 946 644 -302 1.469
OClO Chlorine dioxide 2 A1 448 358 -90 1.252
OClO Chlorine dioxide 3 B2 1110 849 -261 1.308
NO- nitric oxide anion 1 Σ 1347 1002 -345 1.345
NO Nitric oxide 1 Σ 1876 1437 -439 1.306
NO2 Nitrogen dioxide 1 A1 1318 978 -340 1.348
NO2 Nitrogen dioxide 3 B2 1618 657 -961 2.464
NO2+ Nitrogen dioxide cation 1 Σg 1397 1083 -313 1.289
NO2+ Nitrogen dioxide cation 2 Σu 2362 1673 -689 1.412
NO2+ Nitrogen dioxide cation 3 Πu 639 463 -176 1.379
BCl3+ Boron Trichloride cation 3 E' 1104 633 -471 1.745
NHF2 difluoramine 4 A' 500 398 -102 1.257
N2O4 Dinitrogen tetroxide 1 Ag 1383 1076 -307 1.285
N2O4 Dinitrogen tetroxide 5 B1u 1261 994 -267 1.268
N2O4 Dinitrogen tetroxide 8 B2u 1757 1272 -484 1.381
N2O4 Dinitrogen tetroxide 9 B2u 265 211 -54 1.258
N2O4 Dinitrogen tetroxide 10 B3g 1718 1274 -444 1.348
Li2O dilithium oxide 3 Πu 112 53 -59 2.115
C3 carbon trimer 3 Πu 63 -176 -239 -0.361
PO2 Phosphorus dioxide 3 B2 1328 794 -533 1.671
C4 Carbon tetramer 4 Πg 323 -422 -745 -0.765
C4 Carbon tetramer 5 Πu 160 -27 -187 -5.935
NCl nitrogen monochloride 1 Σ 817 605 -212 1.351
NI3 Nitrogen triiodide 3 E 354 542 188 0.653
BrNO Nitrosyl bromide 1 A' 1799 1283 -516 1.403
NH2- amino anion 1 A1 3122 2478 -644 1.260
NH2- amino anion 3 B2 3190 2513 -677 1.270
KrF2 Krypton difluoride 1 Σg 449 350 -99 1.283
SiH2D2 silane-d2 6 B1 2183 1601 -582 1.364
SiH2D2 silane-d2 8 B2 1601 2214 613 0.723
HOClO Chlorous acid 3 A 978 729 -249 1.342
HOClO Chlorous acid 4 A 592 428 -163 1.382
H3O+ hydronium cation 2 A1 954 272 -682 3.505
HNO Nitrosyl hydride 3 A' 1501 1181 -320 1.271
ClONO2 Chlorine nitrate 1 A' 1737 1262 -474 1.376
ClONO2 Chlorine nitrate 9 torsion A" 124 97 -27 1.275
ClO Monochlorine monoxide 1 Σ 843 665 -177 1.266
BrO+ Bromine monoxide cation 1 Σ 840 642 -198 1.309
B4H10 Tetraborane(10) 11 A1 785 551 -234 1.424
B4H10 Tetraborane(10) 12 A1 559 252 -307 2.217
B4H10 Tetraborane(10) 19 A2 662 422 -240 1.567
Cl3- trichloride anion 2 Σu 327 261 -66 1.254
AlCN Aluminum monocyanide 3 Π 132 271 139 0.486
B5H9 pentaborane9 13 B1 240 619 379 0.388
B5H9 pentaborane9 16 B2 1036 767 -269 1.350
B5H9 pentaborane9 18 B2 600 437 -163 1.372
B5H9 pentaborane9 22 E 1409 1091 -318 1.291
CaS Calcium sulfide 1 Σ 459 335 -123 1.367
OPCl Phosphorus oxychloride 2 A' 308 471 163 0.653
OPCl Phosphorus oxychloride 3 A' 492 297 -195 1.656
S2N2 Disulfur dinitride 3 B1u 656 522 -134 1.256
S2N2 Disulfur dinitride 4 B2u 790 613 -177 1.289
Na2 Sodium diatomic 1 Σg 158 121 -37 1.306
H2POH Phosphinous acid 9 A" 375 210 -165 1.785
H2NN Isodiazene 3 A1 1574 1259 -315 1.250
Mg2 Magnesium diatomic 1 Σg 48 30 -18 1.601
CHFCl Chlorofluoromethyl radical 6 A 540 368 -172 1.467
C5H6 Propellane 9 A2" 615 475 -140 1.296
BrONO2 Bromine nitrate 1 A' 1714 1252 -462 1.369
BrONO2 Bromine nitrate 8 A" 728 579 -149 1.258
ZnCH3 Zinc monomethyl 6 E 315 605 290 0.521
NH2NN+ hydrazoic acid, protonated 6 A' 489 227 -262 2.154
H2CNCN cyanamide, methylene 3 A' 2208 2951 743 0.748
H2CNCN cyanamide, methylene 4 A' 1621 2141 520 0.757
SNO Nitrogen oxide sulfide 1 A' 1527 1133 -395 1.348
SNO Nitrogen oxide sulfide 3 A' 792 456 -336 1.736
ONNO NO dimer 1 A1 1868 1336 -532 1.398
ONNO NO dimer 2 A1 239 433 194 0.553
ONNO NO dimer 3 A1 135 302 168 0.445
ONNO NO dimer 4 torsion A2 117 195 78 0.599
ONNO NO dimer 5 B2 1789 1244 -545 1.438
ONNO NO dimer 6 B2 429 641 212 0.670
INO Nitrosyl iodide 1 A' 1785 1263 -522 1.414
INO Nitrosyl iodide 2 A' 216 482 266 0.449
INO Nitrosyl iodide 3 A' 470 248 -222 1.895
AlNC Aluminum isocyanide 3 Π 100 143 43 0.699
ClONO chlorine nitrite 1 A' 1715 1314 -401 1.305
BrOO Bromine dioxide 1 A' 1487 738 -749 2.016
BrONO Bromine nitrite 1 A' 1723 1322 -402 1.304
ONONO Nitrosyl nitrite 1 A1 1740 1331 -409 1.307
ONONO Nitrosyl nitrite 6 B1 140 103 -37 1.364
ONONO Nitrosyl nitrite 7 B2 1697 1275 -422 1.331
ONONO Nitrosyl nitrite 9 B2 380 575 195 0.661