return to home page Computational Chemistry Comparison and Benchmark DataBase Release 18 (October 2016) 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
CH3COOH Acetic acid 18 A" 93 64 -29 1.455
CH3OH Methyl alcohol 12 A" 200 299 99 0.669
C2H6O2S Dimethyl sulfone 20 B1 262 189 -73 1.384
CH3COOCH3 methyl acetate 27 A" 110 29 -81 3.731
CF2CCl2 difluorodichloroethylene 7 B1 1327 574 -753 2.311
CF2CCl2 difluorodichloroethylene 8 B1 989 316 -673 3.134
CF2CCl2 difluorodichloroethylene 11 B2 564 439 -125 1.284
CF2CCl2 difluorodichloroethylene 12 B2 323 175 -148 1.844
C5H12 Pentane 23 A2 131 104 -27 1.256
C5H8 Cyclopentene 18 A' 254 131 -123 1.938
CH3CCCH3 2-Butyne 16 E" 371 295 -76 1.257
C3H6O Oxetane 18 B1 90 44 -46 2.034
C4H2 Diacetylene 7 Πg 482 177 -305 2.723
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 12 B2 533 400 -133 1.334
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 8 B1 1209 330 -879 3.665
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 6 A2 351 537 186 0.654
C5H12 Propane, 2,2-dimethyl- 12 T1 203 304 101 0.668
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
C4N2 2-Butynedinitrile 7 Πg 263 198 -65 1.330
NaOH sodium hydroxide 3 Π 300 130 -170 2.305
SiF2+ Silicon difluoride cation 2 A1 350 261 -89 1.343
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
H2CCCCH2 Butatriene 16 B3g 330 151 -179 2.184
H2CCCCH2 Butatriene 10 B2g 544 429 -115 1.268
CHCl2 dichloromethyl radical 4 A' 190 291 101 0.652
C4H6 Methylenecyclopropane 17 B1 360 271 -89 1.328
ClFO3 Perchloryl fluoride 6 E 405 325 -80 1.248
BrF5 bromine pentafluoride 6 B2 281 206 -75 1.361
PCl5 Phosphorus pentachloride 2 A1' 370 271 -99 1.366
PCl5 Phosphorus pentachloride 7 E' 100 80 -20 1.252
C2H4O4 Formic acid dimer 13 Au 1050 75 -975 14.094
ClOO chloroperoxy radical 3 A' 201 94 -107 2.138
Mg2 Magnesium diatomic 1 Σg 51 84 33 0.610
CH3BO Borane, methyloxo- 7 E 897 1372 475 0.654