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Updated: Aug 17, 2026

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Published on: September 17, 2021
Density-functional theory and Monte Carlo simulation for the surface structure and correlation functions of freely
Zhidong Li1, Dapeng Cao, Jianzhong Wu
1Department of Chemical and Environmental Engineering, University of California, Riverside, 92521-0425, USA.
Abstract:
We present a nonlocal density-functional theory of polymeric fluids consisting of freely jointed Lennard-Jones chains with explicit consideration of the segment size, van der Waals attraction, and structural correlations due to chain connectivity. The excess Helmholtz energy functional is derived from a modified fundamental measure theory for the short-ranged repulsion and the first-order thermodynamic perturbation theory for chain connectivity. The contribution of the long-ranged attraction to the Helmholtz energy functional is taken into account using a quadratic density expansion with the direct correlation function obtained from the first-order mean-spherical approximation. The numerical performance of the density-functional theory is compared well with the simulation results from this work as well as those from the literature for the segment-level density profiles and correlation functions of Lennard-Jones chains in slit pores, near isolated nanoparticles, or in bulk.
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