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 B1B95/6-31+G**
Calculated values were scaled by 0.9566.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 171 58 0.660
CH3COOH Acetic acid 18 A" 93 65 -28 1.441
CH3OH Methyl alcohol 12 A" 200 307 107 0.651
C2H6O2S Dimethyl sulfone 20 B1 262 209 -53 1.255
C2H4+ Ethylene cation 4 Au 84 -483 -567 -0.174
CH3COCl Acetyl Chloride 15 A" 166 121 -45 1.369
C3F8 perfluoropropane 13 A2 276 206 -70 1.340
CH3COOCH3 methyl acetate 26 A" 136 89 -47 1.528
CH3COOCH3 methyl acetate 27 A" 110 27 -83 4.076
C3H6O 2-Propen-1-ol 24 A 188 110 -78 1.713
C5H12 Pentane 23 A2 131 104 -27 1.257
C4H8S Thiophene, tetrahydro- 5 A 1464 2950 1486 0.496
C4H8S Thiophene, tetrahydro- 6 A 1441 2950 1509 0.489
C4H8S Thiophene, tetrahydro- 7 A 1321 2932 1611 0.451
C4H8S Thiophene, tetrahydro- 8 A 1276 2932 1656 0.435
C4H8S Thiophene, tetrahydro- 12 A 888 1413 525 0.628
C4H8S Thiophene, tetrahydro- 13 A 829 1303 474 0.636
C4H8S Thiophene, tetrahydro- 14 A 822 1278 456 0.643
C4H8S Thiophene, tetrahydro- 15 A 678 1252 574 0.541
C4H8S Thiophene, tetrahydro- 16 A 472 1230 758 0.384
C4H8S Thiophene, tetrahydro- 17 A 290 1187 897 0.244
C5H8 Cyclopentene 18 A' 254 154 -100 1.650
C4H6O2 2,3-Butanedione 21 Bg 240 100 -140 2.405
C6H4 Benzyne 24 B2 472 370 -102 1.277
C5H12 Propane, 2,2-dimethyl- 12 T1 203 296 93 0.686
C2H3NO3 Oxamic acid 3 A' 2600 3463 863 0.751
C2H3NO3 Oxamic acid 15 A' 328 248 -80 1.322
C2H3NO3 Oxamic acid 17 A" 815 647 -168 1.260
C2H3NO3 Oxamic acid 21 A" 162 67 -95 2.428
C3H6O Oxetane 18 B1 90 -40 -130 -2.228
C3O2 Carbon suboxide 7 Πu 61 155 94 0.393
C5H8 1,4-Pentadiene 16 A 137 284 147 0.483
HCCBr bromoacetylene 5 Π 295 450 155 0.656
CH3SSCH3 Disulfide, dimethyl 13 A 117 87 -30 1.347
C6H6 Benzvalene 10 A1 996 743 -253 1.340
H2CS- thioformaldehyde anion 4 B1 450 282 -168 1.593
SiF2+ Silicon difluoride cation 2 A1 350 267 -83 1.309
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 211 67 0.683
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 344 -112 1.325
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 134 -37 1.275
CH3OO methylperoxy radical 12 A" 170 120 -50 1.414
CH2OH Hydroxymethyl radical 9 A 234 419 185 0.558
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 862 -274 1.317
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 138 -126 1.917
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 96 -262 3.734
HCCN cyanomethylene 5 Π 129 -221 -350 -0.584
CHCl2 dichloromethyl radical 4 A' 190 297 107 0.640
C4H6 Methylenecyclopropane 17 B1 360 281 -79 1.279
N2O3 Dinitrogen trioxide 9 A" 63 136 73 0.463
C3O Tricarbon monoxide 5 Π 109 184 75 0.592
C3 carbon trimer 3 Πu 63 143 80 0.443
LiS Lithium monosulfide 1 Σ 580 -10005 -10585 -0.058
H3O+ hydronium cation 2 A1 954 742 -212 1.285
SiF3 Silicon trifluoride radical 2 A1 406 285 -121 1.425
SiF3 Silicon trifluoride radical 3 E 959 669 -289 1.432
SiF3 Silicon trifluoride radical 4 E 290 -5069 -5359 -0.057
ClOO chloroperoxy radical 2 A' 414 293 -120 1.411
ClOO chloroperoxy radical 3 A' 201 108 -93 1.858
Cl3- trichloride anion 2 Σu 327 251 -76 1.302
OPCl Phosphorus oxychloride 2 A' 308 485 177 0.635
OPCl Phosphorus oxychloride 3 A' 492 296 -196 1.664
H2OH2O water dimer 8 A' 103 155 52 0.664
H2OH2O water dimer 11 A" 108 171 63 0.633
H2OH2O water dimer 12 A" 88 140 52 0.629
F3- trifluoride anion 2 Σu 550 412 -138 1.335
H2POH Phosphinous acid 9 A" 375 261 -115 1.440
ZnCH3 Zinc monomethyl 6 E 315 579 264 0.544