Free energy, of solid

To p. 11. According to N. H. Fletcher, J. Crystal Growth 28, 375 (1975), the free energy of solid - melt interfaces in many systems (e.g., water - ice) is determined above all by the low entropy of the liquid layers adjacent to the solid surface. This loss of entropy occurs because the above layers are more ordered than the melt far from the solid. 

Theoretical calculations of the surface free energy of solids date back to 1928 with the work of Lennard-Jones and Dent 10). Displacements of the positive and negative ions when a given interior layer becomes a surface layer were allowed for by Verwey 11). Calculations by Shuttleworth 12) showed that van der Waals terms make a significant contribution to surface energy. Benson and his co-workers have made an extensive study of alkali-halides 13-16) and of magnesium oxide 17). 

This paper addresses two different sets of observations on the anisotropy of wetting of Pb crystals by its own melt and by Ga-Pb alloys. The observed anisotropies in these cases are due to the anisotropy of the surface free energy of solid Pb and to the intervention of surface phase transitions. 

D. Chatain and J.J. Metois, A New Procedure for the Determination of the Free Energies of Solid-Fluid... 

Fig. 12.4. Free energy of solid sodium as a function of volume at different temperatures. ...

Ya London component of surface free energy of solid... 

Ysv Surface free energy of solid-vapour interface (mN/m). 

Theoretical estimation of the surface free energy of solids... 

H. Jones, The surface energy of solid metals. Metal Sci. J., 5 15-18.L.Z. (1971) Mezey, and J. Giber, The surface free energies of solid chemical elements calculation from internal free enthalpies of atomization, Jpn. J. Appl Phys., 21(11) 1569-1571 (1982)... 

The critical surface tension yc as deduced by using Zisman s approach, is also usually considered as an approximation of the surface free energy of solids. Thus, yc values of 30.8 mN m 1 [63] and 39.0 mN m- 1 [62] have been reported for MC and CA, respectively. However, these values are quite different from those reported by Rowe [59,60], which makes questionable the comparison of values obtained by different techniques. 

The measurement of the surface free energy of solids is a considerably more difficult task than that of liquids. In solids it is usually impossible to reach a thermodynamically reversible increase in the interfacial area, partially due to the high amount of work required for plastic deformation. Nevertheless, a number of methods that allow one to measure (or at least to approximately evaluate) the surface free energy of solids have been developed. 

In Chapter 7 we saw that the fact that minerals are to a good approximation incompressible means that the effect of pressure on the Gibbs free energy of solid phases is very easily calculated. Thus, in general... 

Plasma treatment of PDMS followed by adsorption of self-assembled silane monolayers has enabled us to controllably modify the surface energy of elastomer surfaces as described in the section on the Johnson, Kendall, and Roberts approach to deriving the surface free energy of solids. A similar treatment of silicon substrates has produced a useful, low—hysteresis model substrate for contact angle study. There are three types of PDMS contact angle substrates usually studied fluids baked or otherwise chemisorbed on solids such as glass or metals cross-linked coatings on flexible substrates, such as paper or plastic film PDMS elastomer surfaces. 

IV. Surface Free Energy of Solids Measurement and Applications 136... 

IV. SURFACE FREE ENERGY OF SOLIDS MEASUREMENT AND APPLICATIONS... 

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