Demixing in Temperature Gradients Ludwig-Soret Effect

6 Demixing in Temperature Gradients (Ludwig-Soret Effect) 

In Chapter 4, we introduced transport equations that apply when there are fluxes other than those of matter that contribute to the entropy production. Assuming that both matter and electrons take part in the transport, Eqns. (4.16)-(4.17) have been derived. In non-isothermal systems, we can use the same set of equations but replace 

indicates that the summation is over (n-1) independent fluxes in the n-compo-nent crystal (see Eqn. (4.29)). Qf jj is the (isothermal) energy flux due to the flux of species j. In an isobaric but non-isothermal system, Xj = 

71) constitutes (n-1) differential equations for the spatial distribution of n components in the crystal. The set of equations is complete if the conservation of matter is taken into account. For a binary system (1—2), Eqn. (8.71) is particularly simple to handle since it reduces to 

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