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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 MP4/6-31G(2df,p)
Calculated values were scaled by 1.

Species Name mode int rot Symmetry Experiment Theory difference ratio
C2H2 Acetylene 4 Πg 612 480 -132 1.275
CH2NN diazomethane 6 B1 406 272 -134 1.493
NH2CN cyanamide 5 torsion A' 408 689 281 0.592
C2F2 difluoroacetylene 4 Πg 270 96 -174 2.827
CaO Calcium monoxide 1 Σ 723 1948 1225 0.371
CaF2 Calcium difluoride 2 A1 120 92 -28 1.302
NO Nitric oxide 1 Σ 1876 3481 1605 0.539
N2O3 Dinitrogen trioxide 9 torsion A" 63 172 109 0.366