Gibbs–Thomson equation

As Gibbs -Thomson effect ( named after Josiah Willard Gibbs and William Thomson, not to be confused with the Thomson effect ) is known in physical chemistry a consequence of the interfacial energy. This means that small droplets of liquid ( ie, particles with a strong surface curvature ) have a higher effective vapor pressure as a planar phase boundary ( liquid-gas ) as small droplets at the interface as compared to the volume of liquid is greater.

A generalization of the Gibbs - Thomson effect allows the explanation of Ostwald ripening, in which grow in disperse systems of small particles by diffusion larger particles and smaller dissolve.

The Gibbs -Thomson equation for a particle with radius is:

With

• P - partial pressure of the droplet- forming substance
• PSättigung - saturation pressure of the droplet- forming substance
• - Surface energy of the drop in J / m².
• - Volume of an atom in the droplet or particle number per volume
• T - temperature in Kelvin.

Because of increase of internal pressure by the curved boundary phase (see Young-Laplace equation ), there is in the interior of small particles and a lowering of the melting temperature. This sometimes is referred to as the Gibbs -Thomson effect.

• Thermodynamics