Complete wetting of curved microscopic channels.
We have measured the adsorption of argon films on arrays of microscopic nonlinear cusps and of semicircular channels. In the former case, we observe a distinct crossover from a planarlike to a geometry dependent growth behavior near liquid-vapor bulk coexistence, characterized by a growth exponent chi equal to -0.96+/-0.04 in very good agreement with the predictions of a recent scaling theory [C. Rascon and A. O. Parry, J. Chem. Phys. 112, 5175 (2000)]. The crossover location is also consistent with theory. Instead, on the concave channels we find a much steeper growth near saturation that may signal the formation of two menisci at both sides of the channel bottom.
Bruschi
Lorenzo
L
Dipartimento di Fisica Galileo Galilei, Università di Padova, via Marzolo 8, 35131 Padova, Italy.
Fois
Giovanni
G
Mistura
Giampaolo
G
Tormen
Massimo
M
Garbin
Valeria
V
di Fabrizio
Enzo
E
Gerardino
Annamaria
A
Natali
Marco
M