Curvature-dependent metastability of the solid phase and the freezing-melting hysteresis in pores
2006 (English)In: Physical Review E, ISSN 1539-3755, Vol. 73, no 1Article in journal (Refereed) Published
We recapitulate and generalize the concept of the freezing-melting hysteresis that attributes this phenomenon to a free-energy barrier between metastable and stable states of pore-filling material. In a phenomenological description, we show that under commonly encountered conditions, this renders the freezing-point depression Delta T-f defined by the surface-to-volume ratio S/V, whereas the melting-point depression Delta T-m by the mean curvature kappa of the pore surface, with Delta T-m/Delta T-f=2 kappa(V/S). Employing H-1 NMR cryoporometry, we experimentally demonstrate the linear correlation between Delta T-m and Delta T-f for several liquids with different Delta T-f,T-m imbibed in controlled pore glasses. The results compare favorably to the morphological properties of the glasses determined by other techniques. Our findings suggest a simple method for analyzing the pore morphology from the observed phase transition temperatures.
Place, publisher, year, edition, pages
2006. Vol. 73, no 1
single cylindrical pore, nuclear-magnetic-resonance, size dependence, porous solids, supercooled liquids, small particles, gold particles, water, behavior, glass
IdentifiersURN: urn:nbn:se:kth:diva-15399DOI: 10.1103/PhysRevE.73.011608ISI: 000235008500057ScopusID: 2-s2.0-32944467782OAI: oai:DiVA.org:kth-15399DiVA: diva2:333440
QC 201005252010-08-052010-08-05Bibliographically approved