title: Second-Nearest-Neighbor Correlations from Connection of Atomic Packing Motifs in Metallic Glasses and Liquids.
abstract: Using molecular dynamics simulations, we have studied the atomic correlations characterizing the second peak in the radial distribution function (RDF) of metallic glasses and liquids. The analysis was conducted from the perspective of different connection schemes of atomic packing motifs, based on the number of shared atoms between two linked coordination polyhedra. The results demonstrate that the cluster connections by face-sharing, specifically with three common atoms, are most favored when transitioning from the liquid to glassy state, and exhibit the stiffest elastic response during shear deformation. These properties of the connections and the resultant atomic correlations are generally the same for different types of packing motifs in different alloys. Splitting of the second RDF peak was observed for the inherent structure of the equilibrium liquid, originating solely from cluster connections; this trait can then be inherited in the metallic glass formed via subsequent quenching of the parent liquid through the glass transition, in the absence of any additional type of local structural order. Increasing ordering and cluster connection during cooling, however, may tune the position and intensity of the split peaks.
authors.affiliation: Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Ding
authors.affiliation: Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA.
authors.forename: Evan
authors.initials: E
authors.lastname: Ma
authors.affiliation: Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.|Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Asta
authors.affiliation: Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.|Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA.
authors.forename: Robert O
authors.initials: RO
authors.lastname: Ritchie