This applet calculates the normalized (divided by volume and permittivity of free space) polarizability of the dielectric double sphere having the relative permittivity e and distance between the centers of the spheres d. Note that the polarizability is uniaxially anisotropic, and the polarizability components are different in the axial (z) and transversal (t) directions. The digits shown are correct.
Reference: M. Pitkonen: Polarizability of the dielectric double sphere, Journal of Mathematical Physics, Vol. 47, 102901, 2006.