Gian Marco Tuveri, Stefan Milenkovic, Matteo Ceccarelli, Igor Bodrenko
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引用次数: 0
Abstract
A flexible molecule can adjust its shape to diffuse through a pore having a diameter smaller than its average dimension. The fluctuations of molecular dimensions as well as the rotations of the molecule inside the pores require special attention to the definition of the molecular size descriptors for diffusive transport in the pores. Within the framework of the previously proposed theory of the steric free energy barrier, we suggest an effective spherical model of a molecule of an arbitrary shape and define two size descriptors-the effective average radius of the molecule and its variance. The two geometric parameters effectively encode both the fluctuations of the molecule and its rotation in the pore. Once determined for a molecule, they can be used to estimate the steric free energy in a pore of arbitrary radius. The results can be applied to diffusive transport through biological nanopores as well as to size-exclusion molecular filtering.
期刊介绍:
The Journal of Chemical Physics publishes quantitative and rigorous science of long-lasting value in methods and applications of chemical physics. The Journal also publishes brief Communications of significant new findings, Perspectives on the latest advances in the field, and Special Topic issues. The Journal focuses on innovative research in experimental and theoretical areas of chemical physics, including spectroscopy, dynamics, kinetics, statistical mechanics, and quantum mechanics. In addition, topical areas such as polymers, soft matter, materials, surfaces/interfaces, and systems of biological relevance are of increasing importance.
Topical coverage includes:
Theoretical Methods and Algorithms
Advanced Experimental Techniques
Atoms, Molecules, and Clusters
Liquids, Glasses, and Crystals
Surfaces, Interfaces, and Materials
Polymers and Soft Matter
Biological Molecules and Networks.