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/CEP-121G*
Calculated values were scaled by 0.9694.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 172 59 0.656
C4H10O Ethoxy ethane 12 A1 240 185 -55 1.298
C4H10O Ethoxy ethane 20 A2 137 98 -39 1.402
CH3CONH2 Acetamide 20 A 259 209 -50 1.240
CH3COOH Acetic acid 18 torsion A" 93 65 -28 1.421
CH3OH Methyl alcohol 12 torsion A" 200 321 121 0.622
C2H6O2S Dimethyl sulfone 20 B1 262 195 -67 1.341
C2H4+ Ethylene cation 4 torsion Au 84 -383 -467 -0.220
CHONH2 formamide 12 torsion A" 289 -113 -402 -2.552
CH3SCH3+ dimethyl sulfide cation 15 B1 172 110 -62 1.567
C3F8 perfluoropropane 13 A2 276 213 -63 1.296
CH3COOCH3 methyl acetate 27 torsion A" 110 34 -76 3.278
C6H4Cl2 1,4-dichlorobenzene 30 B3u 122 98 -24 1.240
CH3CH2CH2CH3 Butane 5 Ag 1442 402 -1040 3.586
CH3CH2CH2CH3 Butane 8 Ag 1151 804 -347 1.431
CH3CH2CH2CH3 Butane 35 Bu 964 2981 2017 0.323
C3H6O 2-Propen-1-ol 24 A 188 110 -79 1.717
CH2ClCHO chloroacetaldehyde 15 torsion A 27 53 26 0.505
CH2ClCHO chloroacetaldehyde 15 A" 59 156 97 0.378
C5H12 Pentane 23 A2 131 103 -28 1.266
CHSNH2 thioformamide 12 A" 393 266 -127 1.479
C3F6 hexafluoropropene 21 A" 60 32 -28 1.874
C5H8 Cyclopentene 18 torsion A' 254 137 -117 1.858
C6F6 hexafluorobenzene 7 B2g 719 516 -203 1.394
NH2CN cyanamide 5 torsion A' 408 632 224 0.646
C4H6O2 2,3-Butanedione 9 Ag 614 495 -119 1.241
C4H6O2 2,3-Butanedione 21 torsion Bg 240 101 -139 2.387
C4H2 Diacetylene 6 Πg 627 1350 723 0.464
C4H2 Diacetylene 7 Πg 482 690 208 0.698
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 983 -408 1.415
C6H4 Benzyne 24 B2 472 354 -118 1.334
C5H12 Propane, 2,2-dimethyl- 12 T1 203 298 95 0.681
C2H3NO3 Oxamic acid 3 A' 2600 3464 864 0.751
C2H3NO3 Oxamic acid 15 A' 328 254 -74 1.293
C2H3NO3 Oxamic acid 16 A" 984 780 -204 1.262
C2H3NO3 Oxamic acid 17 A" 815 642 -173 1.268
C2H3NO3 Oxamic acid 18 A" 745 602 -143 1.238
C2H3NO3 Oxamic acid 20 A" 315 242 -73 1.303
C2H3NO3 Oxamic acid 21 A" 162 46 -116 3.507
C3H6O Oxetane 18 B1 90 64 -25 1.392
C3O2 Carbon suboxide 7 Πu 61 172 111 0.355
HCNO fulminic acid 5 torsion Π 224 125 -99 1.789
C5H8 1,4-Pentadiene 16 A 137 288 151 0.475
P(CH3)3 trimethylphosphine 22 E 259 196 -63 1.321
C6H6 Benzvalene 10 A1 996 731 -265 1.362
C2F2 difluoroacetylene 4 Πg 270 179 -91 1.507
H2CS- thioformaldehyde anion 4 B1 450 -143 -593 -3.145
NaOH sodium hydroxide 3 torsion Π 300 207 -93 1.447
SiF2+ Silicon difluoride cation 2 A1 350 267 -83 1.312
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 207 63 0.696
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 346 -110 1.318
CFCl2 dichlorofluoromethyl radical 2 A' 747 585 -162 1.276
C2H+ Ethynyl cation 3 Π 550 787 238 0.698
CH3OO methylperoxy radical 12 torsion A" 170 127 -43 1.338
CH3 Methyl radical 2 torsion A2" 606 450 -157 1.349
C4H9N Cyclobutylamine 21 A' 174 140 -34 1.242
CH2OH Hydroxymethyl radical 9 torsion A 234 418 184 0.560
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 856 -280 1.327
C6H8 (Z)-hexa-1,3,5-triene 19 torsion A2 264 153 -111 1.727
C6H8 (Z)-hexa-1,3,5-triene 24 torsion B1 358 104 -254 3.455
HCCN cyanomethylene 5 Π 129 -278 -407 -0.464
CHCl2 dichloromethyl radical 4 A' 190 284 94 0.669
C4H6 Methylenecyclopropane 17 B1 360 283 -77 1.274
CH2Cl chloromethyl radical 4 B1 402 -166 -568 -2.420
C2Cl2 dichloroacetylene 4 Πg 333 244 -89 1.362
ClFO3 Perchloryl fluoride 6 E 405 318 -87 1.272
BF3+ boron trifluoride cation 5 B2 1791 666 -1125 2.690
MgF2 Magnesium fluoride 3 Πu 165 128 -37 1.288
FNO3 Fluorine nitrate 7 A' 303 448 145 0.677
PCl5 Phosphorus pentachloride 7 E' 100 79 -21 1.268
OClO- Chlorine dioxide anion 2 A1 418 310 -108 1.349
BCl3+ Boron Trichloride cation 3 E' 1104 764 -340 1.446
N2O3 Dinitrogen trioxide 9 torsion A" 63 127 64 0.497
SF5 Sulfur pentafluoride 9 E 387 302 -85 1.283
C3O Tricarbon monoxide 5 Π 109 248 139 0.439
SiC2 Silicon dicarbide 3 B2 196 -97 -294 -2.021
C3 carbon trimer 3 Πu 63 301 238 0.211
C4 Carbon tetramer 4 Πg 323 526 203 0.614
S3 Sulfur trimer 2 A1 281 558 277 0.503
SiH2D2 silane-d2 6 B1 2183 1557 -626 1.402
SiH2D2 silane-d2 8 B2 1601 2154 553 0.743
HSSSH trisulfane 5 A' 240 190 -50 1.266
ClOO chloroperoxy radical 2 A' 414 261 -152 1.583
ClOO chloroperoxy radical 3 A' 201 104 -97 1.935
B4H10 Tetraborane(10) 10 A1 827 650 -177 1.273
B4H10 Tetraborane(10) 11 A1 785 519 -266 1.512
B4H10 Tetraborane(10) 12 A1 559 201 -358 2.777
B4H10 Tetraborane(10) 19 A2 662 390 -272 1.696
Cl3- trichloride anion 2 Σu 327 264 -63 1.241
BH3PH3 borane phosphine 5 A1 572 433 -139 1.320
BH3PH3 borane phosphine 12 E 447 350 -97 1.277
B5H9 pentaborane9 13 B1 240 603 363 0.398
B5H9 pentaborane9 16 B2 1036 769 -267 1.348
B5H9 pentaborane9 18 B2 600 440 -160 1.363
B5H9 pentaborane9 22 E 1409 1059 -350 1.331
OPCl Phosphorus oxychloride 2 A' 308 465 157 0.662
OPCl Phosphorus oxychloride 3 A' 492 281 -211 1.750
H2OH2O water dimer 12 A" 88 58 -30 1.526
H2POH Phosphinous acid 9 A" 375 238 -138 1.579
CHFCl Chlorofluoromethyl radical 6 A 540 380 -160 1.420
H2CNCN cyanamide, methylene 3 A' 2208 2969 761 0.744
H2CNCN cyanamide, methylene 4 A' 1621 2183 562 0.743
C2H3NO Nitrosoethylene 11 A' 490 334 -156 1.466
SNO Nitrogen oxide sulfide 3 A' 792 481 -311 1.647
ONNO NO dimer 2 A1 239 393 153 0.610
ONNO NO dimer 3 A1 135 284 150 0.473
ONNO NO dimer 4 torsion A2 117 213 96 0.549
ONNO NO dimer 6 B2 429 692 262 0.621
AlNC Aluminum isocyanide 3 Π 100 149 49 0.672