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/cc-pVDZ
Calculated values were scaled by 0.9473.

Species Name mode Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 A" 200 328 128 0.610
CHONH2 formamide 12 A" 289 -260 -549 -1.109
C10H8 naphthalene 27 B2g 770 597 -173 1.290
C3H6O 2-Propen-1-ol 24 A 188 105 -83 1.783
C3H6O Oxetane 18 B1 90 34 -56 2.678
HCNO fulminic acid 5 Π 224 -140 -364 -1.601
C6H6 Benzvalene 10 A1 996 729 -267 1.366
H2CS- thioformaldehyde anion 4 B1 450 -186 -636 -2.422
SiF2+ Silicon difluoride cation 2 A1 350 266 -84 1.314
C5H8 1,3-Pentadiene, (Z)- 22 A' 144 209 65 0.690
C5H8 1,3-Pentadiene, (Z)- 31 A" 456 333 -123 1.369
C5H8 1,3-Pentadiene, (Z)- 32 A" 171 116 -55 1.472
CH3 Methyl radical 2 A2" 606 384 -222 1.578
CH2OH Hydroxymethyl radical 9 A 234 428 194 0.547
ClCO carbonyl monochloride 3 A' 335 264 -71 1.270
HCCN cyanomethylene 5 Π 129 -421 -550 -0.306
CHCl2 dichloromethyl radical 4 A' 190 289 99 0.656
OClO- Chlorine dioxide anion 2 A1 418 308 -110 1.357
SiH- silicon monohydride anion 1 Σ 2175 1714 -461 1.269
Cl3- trichloride anion 2 Σu 327 246 -81 1.330
OPCl Phosphorus oxychloride 2 A' 308 474 166 0.650
OPCl Phosphorus oxychloride 3 A' 492 291 -201 1.691
H2POH Phosphinous acid 9 A" 375 230 -145 1.630
Mg2 Magnesium diatomic 1 Σg 51 14 -37 3.676