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 QCISD(T)/6-311G*
Calculated values were scaled by 0.9628.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 350 150 0.571
C2H2 Acetylene 4 Πg 612 326 -286 1.878
CF2CCl2 difluorodichloroethylene 7 B1 1327 553 -774 2.398
CF2CCl2 difluorodichloroethylene 8 B1 989 312 -677 3.172
CF2CCl2 difluorodichloroethylene 11 B2 564 443 -121 1.273
CF2CCl2 difluorodichloroethylene 12 B2 323 181 -142 1.781
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 8 B1 1209 327 -882 3.692
CFClCFCl cis-1,2-dichloro-1,2-difluoroethylene 12 B2 533 405 -128 1.315
C3H6O Oxetane 18 B1 90 -38 -128 -2.379
LiOH lithium hydroxide 3 Π 257 395 139 0.649
NaOH sodium hydroxide 3 Π 300 227 -73 1.324
CH3 Methyl radical 2 A2" 606 428 -178 1.416
CH2OH Hydroxymethyl radical 8 A 482 694 212 0.694
CH2OH Hydroxymethyl radical 9 A 234 459 225 0.510
CH3CO Acetyl radical 3 A' 1875 1427 -448 1.314
CHCl2 dichloromethyl radical 4 A' 190 301 111 0.631
CaF2 Calcium difluoride 2 A1 120 59 -61 2.024
Li2O dilithium oxide 3 Πu 112 56 -56 2.006
CaOH Calcium monohydroxide 2 Σ 353 633 280 0.558
CaOH Calcium monohydroxide 3 Π 609 359 -250 1.697
H2OH2O water dimer 11 A" 108 167 59 0.646
Mg2 Magnesium diatomic 1 Σg 51 20 -31 2.496
Al2 Aluminum diatomic 1 Σg 286 421 135 0.679
CH3BO Borane, methyloxo- 7 E 897 1436 539 0.624