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Bad vibrational frequency predictions

19 02 11 15 45

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 MP4=FULL/daug-cc-pVTZ
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C3O2 Carbon suboxide 7 Πu 61 -39 -100 -1.559
CO+ carbon monoxide cation 1 Σ 2184 2746 562 0.795
CN Cyano radical 1 Σ 2042 2742 700 0.745
C3H4 cyclopropene 6 A1 905 -149 -1054 -6.059
CH2Cl chloromethyl radical 4 B1 402 121 -281 3.314
HNC+ hydrogen isocyanide cation 2 Σ 2195 2706 511 0.811
HN3+ Hydrazoic acid cation 2 A' 1850 2980 1130 0.621
NO Nitric oxide 1 Σ 1876 3278 1402 0.572
NaO2 Sodium superoxide 3 B2 333 644 311 0.517
S3 Sulfur trimer 2 A1 281 575 294 0.488
SiH2D2 silane-d2 6 B1 2183 1642 -541 1.330
SiH2D2 silane-d2 8 B2 1601 2270 669 0.705
NH4 Ammonium radical 1 A1 2552 3072 520 0.831
CHFCl Chlorofluoromethyl radical 6 A 540 409 -131 1.320
ONNO NO dimer 1 A1 1868 316 -1553 5.918
ONNO NO dimer 2 A1 239 187 -52 1.278
ONNO NO dimer 5 B2 1789 541 -1248 3.307