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)/6-311G*
Calculated values were scaled by 0.9626.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 350 150 0.571
C2H2 Acetylene 4 Πg 612 330 -282 1.857
CF2CCl2 difluorodichloroethylene 7 B1 1327 555 -772 2.391
CF2CCl2 difluorodichloroethylene 8 B1 989 312 -677 3.169
CF2CCl2 difluorodichloroethylene 11 B2 564 444 -120 1.272
CF2CCl2 difluorodichloroethylene 12 B2 323 182 -141 1.779
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 8 B1 1209 328 -881 3.687
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 12 B2 533 406 -127 1.314
C3H6O Oxetane 18 B1 90 -36 -126 -2.505
LiOH lithium hydroxide 3 Π 257 396 139 0.648
NaOH sodium hydroxide 3 Π 300 203 -97 1.480
CH3 Methyl radical 2 A2" 606 429 -178 1.414
CH2OH Hydroxymethyl radical 8 A 482 691 209 0.698
CH2OH Hydroxymethyl radical 9 A 234 458 224 0.511
CH3CO Acetyl radical 4 A' 1420 3008 1588 0.472
CHCl2 dichloromethyl radical 4 A' 190 302 112 0.630
CaF2 Calcium difluoride 2 A1 120 59 -61 2.047
Li2O dilithium oxide 3 Πu 112 55 -56 2.016
CaOH Calcium monohydroxide 2 Σ 353 632 279 0.558
CaOH Calcium monohydroxide 3 Π 609 365 -244 1.669
PO Phosphorus monoxide 1 Σ 1233 1924 690 0.641
H2OH2O water dimer 11 A" 108 167 59 0.647
Mg2 Magnesium diatomic 1 Σg 51 21 -31 2.483
Al2 Aluminum diatomic 1 Σg 286 427 141 0.669
CH3BO Borane, methyloxo- 7 E 897 1436 539 0.624