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Updated: Sep 21, 2025

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
New Framework for Computing a General Local Self-Diffusion Coefficient Using Statistical Mechanics
Michelle A Hunter1, Baris Demir1, Charlotte F Petersen1
1Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, Queensland 4072, Australia.
Abstract:
Widely applicable, modified Green-Kubo expressions for the local diffusion coefficient (D) are obtained using linear response theory. In contrast to past definitions in use, these expressions are statistical mechanical results. Molecular simulations of systems with anisotropic diffusion and an inhomogeneous density profile confirm the validity of the results. Diffusion coefficients determined from different expressions in terms of currents and velocity correlations agree in the limit of large systems. Furthermore, they apply to arbitrarily small local regions, making them readily applicable to nanoscale and inhomogeneous systems where knowledge of D is important.
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