Tuning of tetrahedrality in a silicon potential yields a series of monatomic (metal-like) glassformers of very high fragility

Valeria Molinero; Srikanth Sastry; C. Austen Angell

doi:10.1103/physrevlett.97.075701

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Tuning of tetrahedrality in a silicon potential yields a series of monatomic (metal-like) glassformers of very high fragility

Valeria Molinero·Srikanth Sastry·C. Austen Angell

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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.

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Valeria Molinero, Srikanth Sastry, C. Austen Angell. 2006-08-15. Tuning of tetrahedrality in a silicon potential yields a series of monatomic (metal-like) glassformers of very high fragility. https://doi.org/10.1103/physrevlett.97.075701

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