Molecular dynamics study of a dipolar fluid between charged plates. II

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Abstract
Further molecular dynamics simulations of thin films of Stockmayer molecules between Lennard-Jones plates are discussed when the distance h between the plates ranges from 2.25 σ to 9.5 σ, where σ is the molecular diameter, and the electric field E ranges between 0 and 1010 V/m. The solvation force is calculated as a function of the plate separation h when E=0 and E=109 V/m and as a function of the field E when h=4.0 σ and 7.5 σ. We also study the system when h=2.25 σ and 4.0 σ with the field E ranging from 0 to 1010 V/m and find that the monolayer system (h=2.25 σ) seems to undergo changes of state as the temperature is lowered at zero field or if the field is changed at low temperature. While, in the absence of a field, the molecules tend to form loops and chain-like structures with the dipoles parallel to the wall, a strong external field orients the dipoles along the field so that the long-range repulsive interaction appears to induce a transition to an imperfect (two-dimensional) triangular lattice at low temperature. In between these states, at low temperatures and high fields, the molecules are packed in parallel chains with their moments perpendicular to the field and in ‘‘ferroelectric domains’’ of opposite polarization.