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# Vibrational frequency scaling factors

Calculated vibrational frequencies ("theory" in table) are calculated at ROHF/CEP-31G
Scale factor How many Source
Molecules Vibrations
0.909 ±
Jump to histogram
Formula Name Mode Symmetry Frequency Count
Theory Experiment ratio molecules vibrations

How do we calculate the scaling factor? 2015 08 03 12:34

### 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