A numerical inversion of the perrin equations for rotational diffusion constants for ellipsoids of revolution by iterative techniques.

The rotational diffusion coefficients R(1) and R(3) for ellipsoids of revolution are shown to represent another pair of hydrodynamic data to obtain size and shape with theories by Sadron and Scheraga-Mandelkern. An iterative numerical technique is presented which allows the semiaxes to be determined from the Perrin equations for rotational diffusion constants. The use of this inversion technique is illustrated by application to literature data from dielectric dispersion studies.