Vibrational frequency scaling factors
Calculated vibrational frequencies ("theory" in table) are calculated at
PBEPBE_cp_opt/6311G**
Scale factor 
How many 
Source 
Molecules 
Vibrations 
0.991 ± 0.025 


from cp uncorr. 
Jump to histogram
Formula 
Name 
Mode 
Symmetry 
Frequency 
Count

Theory 
Experiment 
ratio 
molecules 
vibrations 
How do we calculate the scaling factor?
Histogram of vibrational frequency ratios
Ratios greater than 1.35 are in the 1.35 bin.
Ratios less than 0.7 are in the 0.7 bin.

20 











































15 











































10 











































5 











































0 










































 
0.70 
0.75 
0.80 
0.85 
0.90 
0.95 
1.00 
1.05 
1.10 
1.15 
1.20 
1.25 
1.30 
1.35 
Ratio of experimental frequency to calculated frequency 