Soret-Type Motion of Macromolecules in Solution

Abstract

We show that by using a simple optical method, thermodiffusion processes can be exploited for an accurate, reasonably fast determination of the diffusion coefficient $D$ for various macromolecules in solution. As a byproduct, reliable values for the thermal-diffusion ratio $k_T$ are also derived. Furthermore, we report experimental evidence of a new type of convective instability generated in a dilute solution of macromolecules heated from above.