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 B3PW91/aug-cc-pVDZ
Calculated values were scaled by 0.9646.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 180 67 0.629
CH3CONH2 Acetamide 20 A 259 203 -56 1.274
C2H6O2S Dimethyl sulfone 20 B1 262 189 -73 1.384
CH3COOH Acetic acid 18 A" 93 64 -29 1.455
CH3OH Methyl alcohol 12 A" 200 299 99 0.669
CH3COOCH3 methyl acetate 27 A" 110 29 -81 3.731
C5H12 Pentane 23 A2 131 104 -27 1.256
C4H8S Thiophene, tetrahydro- 17 A 290 1185 895 0.245
C4H8S Thiophene, tetrahydro- 16 A 472 1223 751 0.386
C4H8S Thiophene, tetrahydro- 15 A 678 1242 564 0.546
C4H8S Thiophene, tetrahydro- 14 A 822 1274 452 0.645
C4H8S Thiophene, tetrahydro- 13 A 829 1300 471 0.637
C4H8S Thiophene, tetrahydro- 12 A 888 1404 516 0.632
C4H8S Thiophene, tetrahydro- 8 A 1276 2942 1666 0.434
C4H8S Thiophene, tetrahydro- 7 A 1321 2943 1622 0.449
C4H8S Thiophene, tetrahydro- 6 A 1441 2957 1516 0.487
C4H8S Thiophene, tetrahydro- 5 A 1464 2958 1494 0.495
C5H8 Cyclopentene 18 A' 254 131 -123 1.938
C4H2 Diacetylene 7 Πg 482 177 -305 2.723
C5H12 Propane, 2,2-dimethyl- 12 T1 203 304 101 0.668
CH3CCCH3 2-Butyne 16 E" 371 295 -76 1.257
C3H6O Oxetane 18 B1 90 44 -46 2.034
C2H3NO3 Oxamic acid 3 A' 2600 3466 866 0.750
C2H3NO3 Oxamic acid 15 A' 328 255 -73 1.284
C2H3NO3 Oxamic acid 17 A" 815 654 -161 1.247
C2H3NO3 Oxamic acid 21 A" 162 67 -95 2.428
C5H8 1,4-Pentadiene 16 A 137 286 149 0.479
C6H6 Benzvalene 10 A1 996 737 -259 1.352
H2CS- thioformaldehyde anion 4 B1 450 295 -155 1.526
C4N2 2-Butynedinitrile 7 Πg 263 198 -65 1.330
SiF2+ Silicon difluoride cation 2 A1 350 261 -89 1.343
NaOH sodium hydroxide 3 Π 300 130 -170 2.305
C2H Ethynyl radical 3 Π 372 197 -175 1.888
CH2OH Hydroxymethyl radical 9 A 234 390 156 0.600
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 103 -255 3.462
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 169 -95 1.559
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 866 -270 1.312
C4H6 Methylenecyclopropane 17 B1 360 271 -89 1.328
CHCl2 dichloromethyl radical 4 A' 190 291 101 0.652
ClFO3 Perchloryl fluoride 6 E 405 325 -80 1.248
H2CCCCH2 Butatriene 10 B2g 544 429 -115 1.268
H2CCCCH2 Butatriene 16 B3g 330 151 -179 2.184
OClO- Chlorine dioxide anion 2 A1 418 331 -87 1.264
PCl5 Phosphorus pentachloride 7 E' 100 80 -20 1.252
ClOO chloroperoxy radical 3 A' 201 94 -107 2.138
OPCl Phosphorus oxychloride 2 A' 308 473 165 0.652
OPCl Phosphorus oxychloride 3 A' 492 283 -209 1.739
Mg2 Magnesium diatomic 1 Σg 51 84 33 0.610
ZnCN Zinc monocyanide 3 Π 212 168 -44 1.265