title: Dynamics of vacancies in two-dimensional Lennard-Jones crystals.
abstract: Vacancies represent an important class of crystallographic defects, and their behaviors can be strongly coupled with relevant material properties. In this work, we study the dynamics of generic n-point vacancies in two-dimensional Lennard-Jones crystals in several thermodynamic states. Simulations reveal the spectrum of distinct, size-dependent vacancy dynamics, including the nonmonotonously varying diffusive mobilities of one-, two- and three-point vacancies, and several healing routines of linear vacancies. Specifically, we numerically observe significantly faster diffusion of the two-point vacancy that can be attributed to its rotational degree of freedom. The high mobility of the two-point vacancies opens the possibility of doping two-point vacancies into atomic materials to enhance atomic migration. The rich physics of vacancies revealed in this study may have implications in the engineering of defects in extensive crystalline materials for desired properties.
authors.affiliation: Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208-3108, USA.
authors.forename: Zhenwei
authors.initials: Z
authors.lastname: Yao
authors.affiliation: Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208-3108, USA and Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3108, USA and Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208-3108, USA and Department of Physics, Northwestern University, Evanston, Illinois 60208-3108, USA.
authors.forename: Monica Olvera
authors.initials: MO
authors.lastname: de la Cruz