World beyond the nearest neighbors.

Area of Science:

• Materials Science
• Condensed Matter Physics
• Chemical Physics

Background:

• Medium-range order (MRO) describes atomic arrangements beyond nearest neighbors in liquids and glasses.
• Conventional models attribute MRO to short-range order (SRO).
• A new perspective is needed to fully understand liquid and glass structures.

Purpose of the Study:

• To propose a novel dual framework for characterizing MRO in liquids and glasses.
• To investigate the interplay between bottom-up (SRO-driven) and top-down (density wave-driven) approaches.
• To explore how this dual framework influences MRO stability and mechanical properties.

Main Methods:

• Conceptual framework integrating bottom-up and top-down perspectives.
• Analysis of density wave formation driven by global collective forces.
• Investigating the compromise between conflicting approaches to MRO formation.

Main Results:

• A novel dual framework combining SRO-driven and density wave-driven approaches.
• Density waves provide stability and stiffness to MRO.
• The proposed framework offers a new way to describe liquid and glass structure and dynamics.

Conclusions:

• The dual framework provides a more comprehensive understanding of MRO in liquids and glasses.
• Global collective forces driving density waves are crucial for MRO stability.
• This approach offers novel insights into the mechanical properties of liquids and glasses.