Filling and Wetting Transitions at Grooved Substrates

0425956 - ÚCHP 2014 RIV GB eng J - Journal Article
Malijevský, Alexandr
Filling and Wetting Transitions at Grooved Substrates.
Journal of Physics-Condensed Matter. Roč. 25, č. 44 (2013), s. 445006. ISSN 0953-8984. E-ISSN 1361-648X
R&D Projects: GA ČR GA13-09914S
Institutional support: RVO:67985858
Keywords : density-functional * theory * capillary
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 2.223, year: 2013

The wetting and filling properties of a fluid adsorbed on a solid grooved substrate are studied by means of a microscopic density functional theory. The grooved substrates are modelled using a solid slab, interacting with the fluid particles via long-range dispersion forces, to which a one-dimensional array of infinitely long rectangular grooves is sculpted. By investigating the effect of the groove periodicity and the width of the grooves and the ridges, a rich variety of different wetting morphologies is found. In particular, we show that for a saturated ambient gas, the adsorbent can occur in one of four wetting states characterized by (i) empty grooves, (ii) filled grooves, (iii) a formation of mesoscopic hemispherical caps (iv) a macroscopically wet surface. The character of the transition between particular regimes, that also extend off-coexistence, sensitively depends on the model geometry. The temperature at which the system becomes completely wet is considerably higher than that for a flat wall.
Permanent Link: http://hdl.handle.net/11104/0231741