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 B3LYP/CEP-31G*
Calculated values were scaled by 0.9657.

Species Name mode Symmetry Experiment Theory difference ratio
C3H4O2 β–Propiolactone 21 A" 113 175 62 0.646
CH3CONH2 Acetamide 20 A 259 193 -66 1.342
CH3COOH Acetic acid 18 A" 93 71 -22 1.316
CH3OH Methyl alcohol 12 A" 200 319 119 0.627
CH3COCH3 Acetone 12 A2 77 15 -62 5.206
C2H6O2S Dimethyl sulfone 20 B1 262 193 -69 1.356
C2H4+ Ethylene cation 4 Au 84 -323 -407 -0.261
CHONH2 formamide 12 A" 289 -140 -429 -2.055
CH3NO2 Methane, nitro- 11 A" 1583 3073 1490 0.515
C3F8 perfluoropropane 13 A2 276 211 -65 1.306
CH3COOCH3 methyl acetate 27 A" 110 43 -67 2.584
CF2CCl2 difluorodichloroethylene 7 B1 1327 508 -819 2.612
CF2CCl2 difluorodichloroethylene 8 B1 989 299 -690 3.309
CF2CCl2 difluorodichloroethylene 11 B2 564 427 -137 1.321
CF2CCl2 difluorodichloroethylene 12 B2 323 172 -151 1.878
C3H6O 2-Propen-1-ol 24 A 188 108 -80 1.748
C5H12 Pentane 23 A2 131 105 -26 1.251
C5H8 Cyclopentene 18 A' 254 178 -76 1.428
C5H8 Spiropentane 8 A2 919 712 -207 1.291
C2H3N3 1H-1,2,4-Triazole 18 A" 640 515 -125 1.243
C2H4O3 trioxolane124 21 B 193 153 -40 1.261
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 8 B1 1209 319 -890 3.794
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 12 B2 533 392 -141 1.361
C6F6 hexafluorobenzene 7 B2g 715 556 -159 1.285
C6F6 hexafluorobenzene 8 B2g 243 171 -72 1.419
C6F6 hexafluorobenzene 20 E2u 175 127 -48 1.373
NH2CN cyanamide 5 A' 408 625 217 0.653
C4H6O2 2,3-Butanedione 9 Ag 614 493 -121 1.245
C4H6O2 2,3-Butanedione 21 Bg 240 108 -132 2.223
C6H4 Benzyne 24 B2 472 292 -180 1.617
C5H12 Propane, 2,2-dimethyl- 12 T1 203 299 96 0.680
C2H3NO3 Oxamic acid 3 A' 2600 3465 865 0.750
C2H3NO3 Oxamic acid 15 A' 328 251 -77 1.307
C2H3NO3 Oxamic acid 16 A" 984 783 -201 1.256
C2H3NO3 Oxamic acid 17 A" 815 637 -178 1.280
C2H3NO3 Oxamic acid 18 A" 745 595 -150 1.251
C2H3NO3 Oxamic acid 20 A" 315 240 -75 1.314
C2H3NO3 Oxamic acid 21 A" 162 51 -111 3.167
CH3CCCH3 2-Butyne 16 E" 371 263 -108 1.412
C3O2 Carbon suboxide 7 Πu 61 182 121 0.335
HCNO fulminic acid 5 Π 224 110 -114 2.043
C5H8 1,4-Pentadiene 16 A 137 286 149 0.478
CH3SCH2CH3 Ethane, (methylthio)- 18 A' 227 182 -45 1.247
CH3SSCH3 Disulfide, dimethyl 13 A 117 92 -25 1.268
NaOH sodium hydroxide 3 Π 300 239 -61 1.253
SiF2+ Silicon difluoride cation 2 A1 350 268 -82 1.306
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 210 66 0.684
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 339 -117 1.344
C2H Ethynyl radical 3 Π 372 1500 1129 0.248
C2H+ Ethynyl cation 3 Π 550 1038 488 0.529
CH3OO methylperoxy radical 12 A" 170 132 -38 1.284
CH3 Methyl radical 2 A2" 606 473 -134 1.283
CH2OH Hydroxymethyl radical 9 A 234 411 177 0.569
C6H8 (Z)-hexa-1,3,5-triene 11 A1 1136 858 -278 1.324
C6H8 (Z)-hexa-1,3,5-triene 19 A2 264 166 -98 1.594
C6H8 (Z)-hexa-1,3,5-triene 24 B1 358 110 -248 3.269
HCCF Fluoroacetylene 5 Π 367 292 -75 1.255
H2CCCCH2 Butatriene 16 B3g 330 140 -190 2.350
CHCl2 dichloromethyl radical 4 A' 190 283 93 0.672
C4H6 Methylenecyclopropane 17 B1 360 277 -83 1.299
C2Cl2 dichloroacetylene 4 Πg 333 242 -91 1.377
ClFO3 Perchloryl fluoride 6 E 405 324 -81 1.252
PCl5 Phosphorus pentachloride 2 A1' 370 262 -108 1.412
PCl5 Phosphorus pentachloride 7 E' 100 78 -22 1.283
N2O3 Dinitrogen trioxide 9 A" 63 126 63 0.500
SF5 Sulfur pentafluoride 9 E 387 306 -81 1.265
C3 carbon trimer 3 Πu 63 291 228 0.218
C4 Carbon tetramer 4 Πg 323 473 150 0.683
SiH- silicon monohydride anion 1 Σ 2175 1725 -450 1.261
SF5Cl sulfur chloropentafluoride 5 B1 625 439 -186 1.424
SF5Cl sulfur chloropentafluoride 7 B2 505 297 -208 1.698
SF5Cl sulfur chloropentafluoride 11 E 397 234 -163 1.698
C2H4O4 Formic acid dimer 13 Au 1050 76 -974 13.861
ClOO chloroperoxy radical 2 A' 414 259 -155 1.598
ClOO chloroperoxy radical 3 A' 201 102 -99 1.973
H2OH2O water dimer 8 A' 103 158 55 0.654
H2OH2O water dimer 12 A" 88 140 52 0.628
H2POH Phosphinous acid 9 A" 375 251 -124 1.493
CH3BO Borane, methyloxo- 7 E 897 1421 524 0.631