For decades the behavior of Tolman's length (a curvature-correction coefficient in the surface tension ) has remained one of the most controversial issues in mesoscopic thermodynamics of fluids. Moreover, it was commonly believed that Tolman’s length played no significant role in practice. However, it was recently shown  that there is a thermodynamic relation between Tolman’s length and the thickness of the interface on the one hand and the shape of the fluid-phase coexistence on the other hand. In particular, it was shown that Tolman's length strongly diverges at the critical point of fluids with the amplitude that depends on the degree of asymmetry in fluid-phase coexistence. The critical divergence of Tolman’s length is universal, originating from the mesoscopic critical fluctuations. The fluctuations make the fluid interface fuzzy and significantly change the shape of the phase coexistence. In symmetric systems, such as the lattice gas, the curvature correction to the interfacial tension vanishes. The divergence of the curvature correction to the interfacial tension is especially pronounced in polymer solutions and asymmetric polymer blends. Tolman’s length in polymer solutions may become as large as the thickness of the smooth interface, thus playing a significant role in the behavior of polymer microdroplets and polymer fluids in porous media.  R. C. Tolman, J. Chem Phys. 1949, 17, 333.  M. A. Anisimov, Phys. Rev. Lett. 2007, 98, 035702.
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