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 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
HCN+ hydrogen cyanide cation 3 Π 760 1712 952 0.444
C10H8 naphthalene 12 Au 581 410 -171 1.417
C10H8 naphthalene 27 B2g 770 402 -368 1.914
C10H8 naphthalene 28 B2g 461 -368 -829 -1.254
F2CCCF2 tetrafluoroallene 5 B2 2052 701 -1351 2.929
F2CCCF2 tetrafluoroallene 6 B2 1030 562 -468 1.834
F2CCCF2 tetrafluoroallene 7 B2 581 377 -204 1.540
C3H6O Oxetane 18 B1 90 -38 -128 -2.379
HCCBr bromoacetylene 4 Π 618 481 -137 1.285
HCCBr bromoacetylene 5 Π 295 165 -130 1.789
C6H6 Benzvalene 10 A1 996 731 -265 1.362
H2CS- thioformaldehyde anion 4 B1 450 -154 -604 -2.931
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
N2O Nitrous oxide 1 Σ 2282 1243 -1039 1.835
N2O Nitrous oxide 2 Σ 1298 2194 895 0.592
OClO- Chlorine dioxide anion 1 A1 790 634 -156 1.247
OClO- Chlorine dioxide anion 2 A1 418 298 -120 1.403
Li2O dilithium oxide 3 Πu 112 56 -56 2.006
OPCl Phosphorus oxychloride 2 A' 308 462 154 0.667
OPCl Phosphorus oxychloride 3 A' 492 292 -200 1.684
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