The Critical Role of Long-Range Strain-Induced Interactions in Stabilizing Zener Ordering

As a fundamental theory of structural transformations, the Zener ordering of interstitials in a body-centered cubic host lattice, which was established more than half a century ago, has been challenged by recent first-principles investigations. In this Letter, we rigorously prove the existence of Zener ordering via Monte Carlo simulations with complete interstitial interactions and demonstrate the critical role of long-range indirect strain-induced interactions in stabilizing Zener ordering. These insights improve our understanding of the self-induced collective ordering of point defects in a host lattice and elucidate the fundamental physics of order-disorder phase transitions in alloys.