Temperature-driven self-assembly in a hexagonal mesophase-forming model: a dynamic and structural study

Abstract

We investigate the self-assembly and phase transitions of a binary-particle system that forms a hexagonal mesophase, modeled via isotropic Stillinger–Weber interactions and studied with molecular dynamics simulations. Two characteristic temperatures emerge: the order–disorder transition T_OD, marking the onset of hexagonal order, and a higher temperature T_x where wormlike clustering of the minority component first appears in the isotropic phase. Using three complementary methods—(i) angular characterization, (ii) dynamic correlation analysis, and (iii) neighbor permanence time—we show how wormlike aggregates evolve below T_x and eventually align into the ordered mesophase at T_OD. These results clarify the interplay among clustering, dynamic organization, and structural signals in driving mesophase formation, offering insights into the fundamental mechanisms governing self-assembly in complex materials.