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Basic Data Analysis with OTOKO

1) Radii of gyration

A useful rule of thumb to keep in mind when calculating radii of gyration (Rg) is the following:

            (2p)*(s)*Rg or Q*Rg should be less than or equal to 1.

Note: this is a theoretical limit, in practice some studies have taken the maximum allowable value to be 1.5 or higher.   Regardless, the plot should contain a significant number of points at s values less than:

            [(radius of gyration)*(2p)]^-1

OTOKO does provide ways of making a number of different kind of plots including the simple Guinier plot performed by SAPOKO, for instance the OTOKO command ".gui". The command will indicate what maximum s value you are using in your Guinier plot. In the example below, 2p*smax*Rg=1.016.

Using ".plc", one can obtain other plots including Kratky plot.