Facet ridge end points in crystal shapes

Area of Science:

• Surface science
• Condensed matter physics
• Computational materials science

Background:

• Equilibrium crystal shapes (ECS) are fundamental to understanding crystal growth and surface properties.
• Facet ridge end points (FRE) are critical junctures where crystal facets meet.
• Previous models suggested simple stochastic FRE points, potentially simplifying local ECS analysis.

Purpose of the Study:

• To numerically investigate the complexity of equilibrium crystal shapes (ECS) near facet ridge end points (FRE).
• To test the stability of the simplified stochastic FRE point model.
• To characterize the generic shapes and boundaries occurring at FRE.

Main Methods:

• Numerical simulation of a body-centered solid-on-solid model on a square lattice.
• Utilizing an enhanced uniaxial interaction range to probe model behavior.
• Analysis of crystal shapes and boundary transitions.

Main Results:

• Generic equilibrium crystal shapes near FRE are found to be more complex than predicted by the stochastic model.
• Observed complex shapes include first-order faceted-to-rough boundaries.
• These boundaries terminate in Pokrovsky-Talapov-type end points, and internal ridges indicate coexisting rough surface orientations.

Conclusions:

• The simplified stochastic FRE point model is unstable for generic crystal shapes.
• Complex boundaries and internal structures are characteristic of ECS near FRE.
• This finding necessitates more sophisticated models for understanding crystal surface morphology.