TY - JOUR
T1 - Properties of model atomic free-standing thin films
AU - Shi, Zane
AU - Debenedetti, Pablo G.
AU - Stillinger, Frank H.
N1 - Funding Information:
P.G.D. gratefully acknowledges the support of the Princeton Center for Complex Materials (National Science Foundation Materials Research Science and Engineering Center Grant No. DMR-0819860) and of the National Science Foundation (Grant No. CHE-0908265).
PY - 2011/3/21
Y1 - 2011/3/21
N2 - We present a computational study of the thermodynamic, dynamic, and structural properties of free-standing thin films, investigated via molecular dynamics simulation of a glass-forming binary Lennard-Jones mixture. An energy landscape analysis is also performed to study glassy states. At equilibrium, species segregation occurs, with the smaller minority component preferentially excluded from the surface. The films interior density and interface width depend solely on temperature and not the initialization density. The atoms at the surface of the film have a higher lateral diffusivity when compared to the interior. The average difference between the equilibrium and inherent structure energies assigned to individual particles, as a function of the distance from the center of the film, increases near the surface. A minimum of this difference occurs in the region just under the liquid-vapor interface. This suggests that the surface atoms are able to sample the underlying energy landscape more effectively than those in the interior, and we suggest a possible relationship of this observation to the recently reported formation of stable glasses by vapor phase deposition.
AB - We present a computational study of the thermodynamic, dynamic, and structural properties of free-standing thin films, investigated via molecular dynamics simulation of a glass-forming binary Lennard-Jones mixture. An energy landscape analysis is also performed to study glassy states. At equilibrium, species segregation occurs, with the smaller minority component preferentially excluded from the surface. The films interior density and interface width depend solely on temperature and not the initialization density. The atoms at the surface of the film have a higher lateral diffusivity when compared to the interior. The average difference between the equilibrium and inherent structure energies assigned to individual particles, as a function of the distance from the center of the film, increases near the surface. A minimum of this difference occurs in the region just under the liquid-vapor interface. This suggests that the surface atoms are able to sample the underlying energy landscape more effectively than those in the interior, and we suggest a possible relationship of this observation to the recently reported formation of stable glasses by vapor phase deposition.
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U2 - 10.1063/1.3565480
DO - 10.1063/1.3565480
M3 - Article
C2 - 21428649
AN - SCOPUS:79953181650
SN - 0021-9606
VL - 134
JO - Journal of Chemical Physics
JF - Journal of Chemical Physics
IS - 11
M1 - 114524
ER -