title: Tuning of tetrahedrality in a silicon potential yields a series of monatomic (metal-like) glass formers of very high fragility.
abstract: We obtain monatomic glass formers in simulations by modifying the tetrahedral character in a silicon potential to explore a triple point zone between potentials favoring diamond (dc) and bcc crystals. dc crystallization is always preceded by a polyamorphic transformation of the liquid, and is frustrated when the Kauzmann temperature of the high temperature liquid intersects the liquid-liquid coexistence line. The glass forming liquids are extraordinarily fragile. Our results suggest that Si and Ge liquids may be vitrified at a pressure close to the diamond-beta-tin-liquid triple point.
authors.affiliation: Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287, USA. valeria.molinero@utah.edu
authors.forename: Valeria
authors.initials: V
authors.lastname: Molinero
authors.forename: Srikanth
authors.initials: S
authors.lastname: Sastry
authors.forename: C Austen
authors.initials: CA
authors.lastname: Angell