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 CCSD(T)/aug-cc-pVTZ
Calculated values were scaled by 0.9699.

Species Name mode Symmetry Experiment Theory difference ratio
C2H4+ Ethylene cation 4 Au 84 -367 -451 -0.229
CHONH2 formamide 12 A" 289 -88 -377 -3.282
CF2CCl2 difluorodichloroethylene 7 B1 1327 554 -773 2.397
CF2CCl2 difluorodichloroethylene 8 B1 989 305 -684 3.239
CF2CCl2 difluorodichloroethylene 11 B2 564 445 -119 1.267
CF2CCl2 difluorodichloroethylene 12 B2 323 177 -146 1.825
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 6 A2 351 518 167 0.678
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 8 B1 1209 326 -883 3.713
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 12 B2 533 403 -130 1.324
HCNO fulminic acid 5 Π 224 -42 -266 -5.389
CH3 Methyl radical 2 A2" 606 482 -125 1.259
CH2OH Hydroxymethyl radical 9 A 234 411 177 0.569
CHCl2 dichloromethyl radical 4 A' 190 294 104 0.647
NO2 Nitrogen dioxide 1 A1 1318 2543 1225 0.518
NO2 Nitrogen dioxide 3 B2 1618 2827 1209 0.572
C3 carbon trimer 3 Πu 63 -44 -108 -1.436
Cl3- trichloride anion 2 Σu 327 252 -75 1.300
H2OH2O water dimer 8 A' 103 150 47 0.685
H2OH2O water dimer 12 A" 88 128 40 0.688
H2POH Phosphinous acid 9 A" 375 253 -122 1.482
Mg2 Magnesium diatomic 1 Σg 51 37 -14 1.385
HCNH+ HCNH+ 2 Σ 3188 -7901 -11088 -0.403
HCNH+ HCNH+ 3 Σ 2156 -23634 -25790 -0.091
HCNH+ HCNH+ 5 Π 646 -18826 -19472 -0.034
CH3BO Borane, methyloxo- 7 E 897 1427 531 0.628