Structural selection rules in self-assembly and self-organization: role of entropy production rate
Hideki Nabika
Abstract
Abstract Self-assembly and self-organization are mechanisms by which ordered structures are formed spontaneously in nature. Traditionally, these phenomena have been distinguished thermodynamically: self-assembly occurs via free energy minimization toward equilibrium, whereas self-organization occurs in open systems maintained far from equilibrium via continuous energy dissipation. Despite this contrast, both processes involve dynamic pathways governed by entropy production during structure formation. Recent findings have shown that the entropy production rate is important in determining the selection rule for the resultant structure. Herein, we first summarize the differences and similarities between self-assembly and self-organization, along with representative examples, from micelles and crystals to convective flows and chemical oscillations. Then, we focus on the entropy production rate as a principle governing structure selection during non-equilibrium processes in both self-assembly and self-organization regimes. Our recent experimental findings reveal how flux conditions influence structure selection in reaction–diffusion systems (Liesegang phenomenon) and protein self-assembly. This perspective suggests that nature, including biological systems, may selectively harness self-assembly or self-organization depending on the interplay between energy flux and the kinetics of the involved reactions. These insights highlight the potential of an entropy-based analysis to enhance our understanding of complex pattern formation and guide the rational design of self-assembly and self-organization.