The structure of frozen phases in slit nanopores: A grand canonical Monte Carlo study
Abstract
Freezing of soft spheres in slit nanopores is investigated using Grand canonical Monte Carlo simulations. The pores are in equilibrium with a liquid located close to the liquidsolid coexistence region in the bulk LennardJones phase diagram. In addition to layering, the confined fluid is found to possess inplane order, leading to the formation of frozen phases which give rise to a sequence of solidsolid transformations as the pore width is varied. Transformations between n layered triangular to n+1 layered square lattices and between n layered square to triangular lattices, are observed for n=1, 2, 3, and 4. The transition from triangular to square lattices occurs via an intermediate buckled phase which is characterized by increased outofplane motion, while maintaining inplane triangular order. Buckling was found to decrease with increasing number of layers. The transition between square to triangular lattices at a fixed number of layers is accompanied by a lowering of the solvation force, resulting in a doublet in the solvation force maxima. Influence of fluidwall interactions on the nature of the frozen phases are studied by comparing the structures formed with a 1043 and 104 fluidwall potential. The solid structures are classified based on their closest 3D counterparts.
 Publication:

Journal of Chemical Physics
 Pub Date:
 September 2002
 DOI:
 10.1063/1.1501120
 Bibcode:
 2002JChPh.117.5373A
 Keywords:

 Monte Carlo Method;
 Nanostructure (Characteristics);
 Phase Diagrams;
 Porous Materials;
 Solvation;
 61.46.+w;
 61.43.Bn;
 SolidState Physics;
 Structural modeling: serialaddition models computer simulation