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 mPW1PW91/cc-pVTZ
Calculated values were scaled by 0.9592.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 179 66 0.633
CH3CONH2 Acetamide 20 A 259 159 -99 1.624
CH3OH Methyl alcohol 12 A" 200 291 91 0.688
CH3COCH3 Acetone 12 A2 77 24 -53 3.235
C2H6O2S Dimethyl sulfone 20 B1 262 202 -60 1.295
C2H4+ Ethylene cation 4 Au 84 -454 -538 -0.185
CHONH2 formamide 12 A" 289 209 -80 1.383
CH3COCl Acetyl Chloride 15 A" 166 132 -34 1.259
C3F8 perfluoropropane 13 A2 276 216 -60 1.276
CH3COOCH3 methyl acetate 27 A" 110 46 -64 2.366
C3H6O 2-Propen-1-ol 23 A 277 220 -57 1.257
C3H6O 2-Propen-1-ol 24 A 188 112 -76 1.680
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 2933 1612 0.450
C4H8S Thiophene, tetrahydro- 8 A 1276 2932 1656 0.435
C4H8S Thiophene, tetrahydro- 12 A 888 1420 532 0.625
C4H8S Thiophene, tetrahydro- 13 A 829 1309 480 0.633
C4H8S Thiophene, tetrahydro- 14 A 822 1288 466 0.638
C4H8S Thiophene, tetrahydro- 15 A 678 1257 579 0.539
C4H8S Thiophene, tetrahydro- 16 A 472 1238 766 0.381
C4H8S Thiophene, tetrahydro- 17 A 290 1195 905 0.243
C5H8 Cyclopentene 18 A' 254 138 -116 1.840
C4H6O2 2,3-Butanedione 21 Bg 240 104 -136 2.301
C5H12 Propane, 2,2-dimethyl- 12 T1 203 301 98 0.674
C2H3NO3 Oxamic acid 3 A' 2600 3479 879 0.747
C2H3NO3 Oxamic acid 15 A' 328 258 -70 1.270
C2H3NO3 Oxamic acid 21 A" 162 65 -97 2.493
C3H6O Oxetane 18 B1 90 41 -48 2.164
CH3OC2H5 Ethane, methoxy- 29 A" 248 196 -52 1.263
C5H8 1,4-Pentadiene 16 A 137 286 149 0.480
C6H6 Benzvalene 10 A1 996 747 -249 1.334
H2CS- thioformaldehyde anion 4 B1 450 211 -239 2.136
NaOH sodium hydroxide 3 Π 300 137 -163 2.190
SiF2+ Silicon difluoride cation 2 A1 350 276 -74 1.268
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 207 63 0.696
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 349 -107 1.307
CH3OO methylperoxy radical 12 A" 170 125 -45 1.358
CH2OH Hydroxymethyl radical 9 A 234 398 164 0.588
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 866 -270 1.312
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 147 -117 1.795
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 97 -261 3.697
HCCN cyanomethylene 5 Π 129 -258 -387 -0.500
CHCl2 dichloromethyl radical 4 A' 190 291 101 0.652
C4H6 Methylenecyclopropane 17 B1 360 288 -72 1.252
N2O3 Dinitrogen trioxide 9 A" 63 138 75 0.457
TiO2 Titanium dioxide 1 A1 959 332 -627 2.885
ClOO chloroperoxy radical 2 A' 414 292 -122 1.417
ClOO chloroperoxy radical 3 A' 201 117 -85 1.724
Cl3- trichloride anion 2 Σu 327 259 -68 1.262
OPCl Phosphorus oxychloride 2 A' 308 487 179 0.632
OPCl Phosphorus oxychloride 3 A' 492 297 -195 1.654
H2POH Phosphinous acid 9 A" 375 261 -114 1.438
Mg2 Magnesium diatomic 1 Σg 51 84 33 0.607