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arXiv · 2508.13918

Order-Disorder Transitions and Thermal Pathways in Frustrated 2D Colloidal Crystals

Alexandre Vargas·Thiago Puccinelli·José Rafael Bordin
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Abstract

We employ extensive NPT molecular dynamics simulations to explore the thermal transitions of two-dimensional colloidal crystals interacting via a core-softened potential with competing length scales. The system stabilizes three distinct solid phases, namely low-density triangular (LDT), stripe, and kagome, which exhibit markedly different responses to heating and cooling. Our simulations reveal that the LDT and kagome phases melt via first-order transitions, but only the former recrystallizes smoothly. The kagome phase displays strong hysteresis and metastability, while the stripe phase undergoes a continuous and nearly reversible transformation. These results highlight the role of lattice geometry and frustration in shaping non-universal melting and freezing pathways in 2D soft matter.

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Alexandre Vargas, Thiago Puccinelli, José Rafael Bordin. 2025-08-19. Order-Disorder Transitions and Thermal Pathways in Frustrated 2D Colloidal Crystals. https://arxiv.org/abs/2508.13918

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