Berlin 2015 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

DS: Fachverband Dünne Schichten

DS 13: Interfaces and Thin Films I (joint session with CPP)

DS 13.1: Talk

Tuesday, March 17, 2015, 10:00–10:15, C 243

What is the result of a tensiometer measurement to do with the surface tension? — •Markus Bier — Max Planck Institute IS and University of Stuttgart, Germany

The surface tension of liquids is routinely measured with various types of tensiometers under ambient pressure conditions [1]. For, e.g., water at room temperture this leads to the well-known value of 0.07 N/m [1]. However, the surface tension is strictly defined only under conditions of liquid-vapour bulk coexistence, whereas, e.g., water at room temperature and ambient pressure is deep in the one-phase region of the phase diagram, far away from phase coexistence. Hence the above-mentioned tensiometer measurements are actually performed at interfaces under non-equilibrium conditions. This leads to the question whether it is legitimate at all to identify the result of a tensiometer measurement of a non-equilibrium interface with the surface tension. This contribution gives an answer to that question [2].

References:
[1] D.R. Lide (ed.), CRC Handbook of Chemistry and Physics, 82nd
[1] edition (CRC Press, Boca Raton, 2001).
[2] M. Bier and D. Arnold, Phys. Rev. E 88, 062307 (2013).