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 B1B95/3-21G*
Calculated values were scaled by 0.9549.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C4H10O Ethoxy ethane 12 A1 240 173 -67 1.388
C4H10O Ethoxy ethane 20 A2 137 104 -33 1.320
C4H10O Ethoxy ethane 28 B1 126 93 -33 1.361
CH3CONH2 Acetamide 20 A 259 391 132 0.662
CH3OH Methyl alcohol 12 torsion A" 200 367 167 0.545
C2H4+ Ethylene cation 4 torsion Au 84 -531 -615 -0.158
CH2I2 Diiodomethane 3 A1 704 486 -218 1.450
CH2I2 Diiodomethane 4 A1 285 110 -175 2.601
CH2I2 Diiodomethane 7 B1 896 704 -192 1.272
CHONH2 formamide 12 torsion A" 289 498 209 0.580
HNCO Isocyanic acid 4 A' 777 572 -204 1.357
HNCO Isocyanic acid 5 A' 577 412 -165 1.401
CH3SCH3+ dimethyl sulfide cation 15 B1 172 121 -51 1.425
C3F8 perfluoropropane 13 A2 276 194 -82 1.421
CH3CH2CH2CH3 Butane 5 Ag 1442 411 -1031 3.507
CH3CH2CH2CH3 Butane 8 Ag 1151 815 -336 1.412
CH3CH2CH2CH3 Butane 30 Bu 1461 2936 1475 0.498
CH3CH2CH2CH3 Butane 35 Bu 964 3005 2041 0.321
C3H6O 2-Propen-1-ol 22 A 377 293 -84 1.288
C3H6O 2-Propen-1-ol 24 A 188 100 -88 1.887
CH2ClCHO chloroacetaldehyde 15 torsion A 27 61 34 0.440
CH2ClCHO chloroacetaldehyde 15 A" 59 179 120 0.329
C2H2O2 Ethanedial 7 torsion Au 127 195 68 0.650
C3F6 hexafluoropropene 13 A' 289 225 -64 1.283
C3F6 hexafluoropropene 21 A" 60 15 -45 3.932
C4H9N Pyrrolidine 36 A" 65 28 -37 2.317
C4H8O2 1,4-Dioxane 19 Au 288 219 -69 1.315
C5H8 Cyclopentene 18 torsion A' 254 133 -121 1.916
KCN Potassium cyanide 3 A' 139 101 -38 1.373
N2H4 Hydrazine 6 A 780 594 -186 1.312
C4H6O2 2,3-Butanedione 21 torsion Bg 240 105 -135 2.293
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 996 -395 1.396
C2N2 Cyanogen 4 Πg 503 755 252 0.667
C5H12 Propane, 2,2-dimethyl- 12 T1 203 310 107 0.654
C2H3NO3 Oxamic acid 3 A' 2600 3369 769 0.772
C2H3NO3 Oxamic acid 15 A' 328 245 -83 1.336
C2H3NO3 Oxamic acid 21 A" 162 116 -46 1.397
C3H6O Oxetane 23 B2 1228 961 -267 1.278
C3O2 Carbon suboxide 7 Πu 61 146 85 0.418
HCNO fulminic acid 5 torsion Π 224 530 306 0.423
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 688 -2390 4.472
C5H8 1,4-Pentadiene 16 A 137 298 161 0.460
C5H8 1,4-Pentadiene 17 torsion A 102 80 -22 1.279
C5H8 1,4-Pentadiene 17 torsion A 102 80 -22 1.279
P(CH3)3 trimethylphosphine 22 E 259 203 -56 1.275
C2H4F2 1,2-difluoroethane 18 Bu 295 215 -80 1.369
C6H6 Benzvalene 10 A1 996 785 -211 1.269
H2CS- thioformaldehyde anion 4 B1 450 236 -214 1.905
C4N2 2-Butynedinitrile 6 Πg 504 907 403 0.556
C4N2 2-Butynedinitrile 8 Πu 472 682 210 0.692
LiOH lithium hydroxide 3 Π 257 409 153 0.627
SiF2+ Silicon difluoride cation 2 A1 350 270 -80 1.296
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 209 65 0.689
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 343 -113 1.328
CFCl2 dichlorofluoromethyl radical 2 A' 747 538 -209 1.389
FCO+ Carbonyl fluoride cation 3 Π 650 500 -150 1.301
C2H Ethynyl radical 3 torsion Π 372 541 170 0.686
CH3 Methyl radical 2 torsion A2" 606 464 -142 1.307
CH2OH Hydroxymethyl radical 9 torsion A 234 424 190 0.552
ClCO carbonyl monochloride 3 A' 335 265 -70 1.263
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 863 -273 1.317
C6H8 (Z)-hexa-1,3,5-triene 19 torsion A2 264 145 -119 1.822
C6H8 (Z)-hexa-1,3,5-triene 24 torsion B1 358 99 -259 3.598
HCCN cyanomethylene 4 Π 383 591 208 0.649
HCCN cyanomethylene 5 Π 129 380 251 0.339
CH3SO2NH2 methanesulfonamide 11 A' 689 504 -185 1.367
NF2 Difluoroamino radical 2 A1 573 455 -118 1.261
CH2Cl chloromethyl radical 4 B1 402 277 -125 1.449
C2Cl2 dichloroacetylene 4 Πg 333 496 163 0.671
HClO4 perchloric acid 12 A" 191 123 -68 1.552
BF3+ boron trifluoride cation 5 B2 1791 708 -1083 2.530
NH3 Ammonia 2 torsion A1 950 683 -267 1.392
H2O2 Hydrogen peroxide 4 torsion A 371 70 -301 5.304
O2+ diatomic oxygen cation 1 Σg 1873 1431 -442 1.309
HN3+ Hydrazoic acid cation 4 A' 850 576 -274 1.475
FOOF Perfluoroperoxide 1 A 1210 956 -254 1.266
FOOF Perfluoroperoxide 4 torsion A 202 160 -42 1.260
FOOF Perfluoroperoxide 5 B 614 938 324 0.655
NF3 Nitrogen trifluoride 4 E 492 390 -102 1.263
BeBr2 Beryllium bromide 3 Πu 207 337 130 0.615
BeF2 Beryllium fluoride 3 Πu 343 252 -91 1.360
CaBr2 Calcium dibromide 3 Πu 72 135 63 0.534
O3 Ozone 2 A1 705 558 -147 1.264
BCl3+ Boron Trichloride cation 3 E' 1104 780 -324 1.416
N2O4 Dinitrogen tetroxide 9 B2u 265 204 -61 1.299
N2O3 Dinitrogen trioxide 9 torsion A" 63 157 94 0.401
C3O Tricarbon monoxide 5 Π 109 192 83 0.567
AsSe Arsenic monoselenide 1 Σ 280 419 139 0.669
Li2O dilithium oxide 3 Πu 112 71 -40 1.568
C3 carbon trimer 3 Πu 63 158 95 0.401
S3 Sulfur trimer 2 A1 281 584 303 0.481
Be(OH)2 Beryllium hydroxide 8 B 456 340 -116 1.340
NI3 Nitrogen triiodide 3 E 354 563 209 0.629
ND3 Ammonia-d3 2 A1 748 520 -228 1.438
NH2- amino anion 1 A1 3122 2578 -544 1.211
NH2- amino anion 3 B2 3190 2620 -571 1.218
SiH2D2 silane-d2 6 B1 2183 1570 -613 1.390
SiH2D2 silane-d2 8 B2 1601 2173 572 0.737
H3O+ hydronium cation 2 A1 954 485 -470 1.970
C2H4O4 Formic acid dimer 2 Ag 2949 2184 -765 1.350
C2H4O4 Formic acid dimer 24 Bu 268 403 135 0.665
NH4 Ammonium radical 2 E 1581 1248 -333 1.266
ClOO chloroperoxy radical 1 A' 1443 1075 -368 1.343
B4H10 Tetraborane(10) 11 A1 785 580 -205 1.353
B4H10 Tetraborane(10) 12 A1 559 248 -311 2.255
B4H10 Tetraborane(10) 19 A2 662 391 -271 1.693
B4H10 Tetraborane(10) 36 B2 236 371 135 0.636
AlCN Aluminum monocyanide 3 Π 132 285 153 0.463
B5H9 pentaborane9 13 B1 240 603 363 0.398
B5H9 pentaborane9 16 B2 1036 784 -252 1.321
B5H9 pentaborane9 18 B2 600 464 -136 1.293
B5H9 pentaborane9 22 E 1409 1061 -348 1.328
OPCl Phosphorus oxychloride 2 A' 308 478 170 0.645
OPCl Phosphorus oxychloride 3 A' 492 293 -199 1.679
H2OH2O water dimer 6 A' 311 527 216 0.590
H2OH2O water dimer 7 A' 143 277 134 0.516
H2OH2O water dimer 8 A' 103 202 99 0.510
H2OH2O water dimer 10 A" 523 852 329 0.614
H2OH2O water dimer 11 A" 108 218 110 0.496
H2POH Phosphinous acid 9 A" 375 223 -152 1.684
Mg2 Magnesium diatomic 1 Σg 48 97 49 0.495
CHFCl Chlorofluoromethyl radical 6 A 540 370 -170 1.461
ZnCH3 Zinc monomethyl 6 E 315 631 316 0.499
H2CNCN cyanamide, methylene 3 A' 2208 2968 760 0.744
H2CNCN cyanamide, methylene 4 A' 1621 2204 583 0.736
C2H3NO Nitrosoethylene 11 A' 490 313 -177 1.564
SNO Nitrogen oxide sulfide 3 A' 792 451 -341 1.756
ONNO NO dimer 2 A1 239 476 236 0.503
ONNO NO dimer 3 A1 135 303 168 0.445
ONNO NO dimer 4 torsion A2 117 221 104 0.529
ONNO NO dimer 5 B2 1789 1419 -370 1.260
ONNO NO dimer 6 B2 429 695 265 0.618
INO Nitrosyl iodide 2 A' 216 512 296 0.422
INO Nitrosyl iodide 3 A' 470 260 -210 1.805
AlNC Aluminum isocyanide 3 Π 100 166 66 0.604
BrOO Bromine dioxide 1 A' 1487 1035 -452 1.437
ONONO Nitrosyl nitrite 9 B2 380 603 223 0.631