Connectivity, dynamics, and structure in a tetrahedral network liquid

Area of Science:

• Computational physics
• Soft matter physics
• Statistical mechanics

Background:

• Understanding the self-assembly and emergent properties of complex fluids is crucial.
• Patchy particles offer a model system for studying network formation and phase transitions.
• Investigating the relationship between structure, dynamics, and connectivity in liquids is an ongoing challenge.

Purpose of the Study:

• To computationally investigate the structure and dynamics of a liquid composed of patchy particles.
• To analyze the formation of an amorphous tetrahedral network as temperature decreases.
• To explore the correlations between particle connectivity, mobility, and diffusion in the liquid.

Main Methods:

• Brownian dynamics simulations were employed to model the liquid of patchy particles.
• Particle connectivity was analyzed by categorizing particles based on their number of bonds (penta-modal distribution).
• System dynamics were studied in both real space (mobility, diffusion) and Fourier space (length scales).

Main Results:

• A temperature-dependent amorphous tetrahedral network structure was observed.
• Particle bonding was found to be correlated, not random, at low temperatures.
• Anomalous diffusion was identified, linked to particle connectivity and short-time hopping of weakly bonded particles.
• Two distinct length scales (dynamic and static) were found to increase with cooling.

Conclusions:

• The low-temperature behavior of this viscoelastic liquid can be explained by an evolving network of metastable cooperative domains.
• Particle connectivity is a key factor governing system dynamics and diffusion.
• The study provides insights into the complex interplay between structure and dynamics in networked liquids.