Intrinsic effects of the boundary condition on switching processes in spin-crossover solids

TL;DR

This paper explores how boundary conditions influence domain growth during spin state switching in spin-crossover solids, revealing unique corner-initiated domain formation under open boundaries due to long-range elastic interactions.

Contribution

It demonstrates the significant impact of boundary conditions on switching dynamics and domain formation in spin-crossover solids with long-range elastic interactions, especially at the nanoscale.

Findings

Domains grow from corners under open boundary conditions.

Boundary conditions drastically alter switching dynamics.

Elastic interactions induce long-range effects influencing domain growth.

Abstract

We investigated domain growth in switching processes between the low-spin and high-spin phases in thermally induced hysteresis loops of spin-crossover (SC) solids. Elastic interactions among the molecules induce effective long-range interactions, and thus the boundary condition plays a significant role in the dynamics. In contrast to SC systems with periodic boundary conditions, where uniform configurations are maintained during the switching process, we found that domain structures appear with open boundary conditions. Unlike Ising-like models with short-range interactions, domains always grow from the corners of the system. The present clustering mechanism provides an insight into the switching dynamics of SC solids, in particular, in nano-scale systems.