Orientation-dependent mutual crystalline and amorphous order in a single phase solid.

Area of Science:

• Materials Science
• Solid-State Chemistry
• Nanotechnology

Background:

• Amorphous materials lack long-range order but possess local structural order.
• Characterizing medium-range order in amorphous materials is challenging.
• Existing models like Zachariasen and crystal competing models describe disordered phases.

Purpose of the Study:

• To investigate the nature of medium-range order in amorphous materials.
• To explore a novel form of organized inorganic matter.
• To reconcile competing models of amorphous structures.

Main Methods:

• Synthesis of a novel 2D amorphous material with 3D crystalline stacking.
• Direct imaging techniques to reveal structural properties.
• Analysis using the Zachariasen model for 2D amorphous systems.

Main Results:

• Demonstrated a material amorphous in 2D (Nb-W-O monolayers) with long-range crystalline order in the third dimension.
• Observed periodic stacking of amorphous monolayers, enabling direct imaging.
• Confirmed the formation of amorphous monolayers consistent with the 2D Zachariasen model.

Conclusions:

• The distinction between crystalline and amorphous materials can extend to principal dimensions within a single solid.
• This work provides new insights into the structural complexity of amorphous materials.
• The findings challenge the conventional understanding of order in disordered matter.