return to home page Computational Chemistry Comparison and Benchmark DataBase Release 19 (April 2018) 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
C10H8 naphthalene 12 Au 581 409 -172 1.420
C10H8 naphthalene 27 B2g 770 402 -368 1.916
C10H8 naphthalene 28 B2g 461 -371 -832 -1.241
F2CCCF2 tetrafluoroallene 5 B2 2052 702 -1350 2.922
F2CCCF2 tetrafluoroallene 6 B2 1030 563 -467 1.831
F2CCCF2 tetrafluoroallene 7 B2 581 378 -203 1.538
C3H6O Oxetane 18 B1 90 -36 -126 -2.505
NaOH sodium hydroxide 3 Π 300 203 -97 1.480
C6H6 Benzvalene 10 A1 996 731 -265 1.363
HCCBr bromoacetylene 4 Π 618 483 -135 1.280
HCCBr bromoacetylene 5 Π 295 168 -127 1.759
H2CS- thioformaldehyde anion 4 B1 450 -148 -598 -3.045
LiOH lithium hydroxide 3 Π 257 396 139 0.648
CH2OH Hydroxymethyl radical 8 A 482 691 209 0.698
CH2OH Hydroxymethyl radical 9 A 234 458 224 0.511
CH3 Methyl radical 2 A2" 606 429 -178 1.414
CaF2 Calcium difluoride 2 A1 120 59 -61 2.047
OClO- Chlorine dioxide anion 2 A1 418 304 -114 1.377
Li2O dilithium oxide 3 Πu 112 55 -56 2.014
CHCl2 dichloromethyl radical 4 A' 190 302 112 0.630
Al2 Aluminum diatomic 1 Σg 286 427 141 0.669
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
OPCl Phosphorus oxychloride 2 A' 308 464 156 0.664
OPCl Phosphorus oxychloride 3 A' 492 293 -199 1.679