Tailoring chemical bonds to design unconventional glasses

• 成果类型: Article
• 署名作者: Raty, Jean -Yves; Bichara, Christophe; Schoen, Carl-Friedrich; Gatti, Carlo; Wuttig, Matthias
• 署名单位: University of Liege; Centre National de la Recherche Scientifique (CNRS); CNRS - Institute of Physics (INP); Aix-Marseille Universite; RWTH Aachen University; Consiglio Nazionale delle Ricerche (CNR); Istituto di Scienze Tecnologie Chimiche Giulio Natta (SCITEC-CNR); Helmholtz Association; Research Center Julich
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-9847
• DOI: 10.1073/pnas.2316498121
• 发表日期: 2024-01-09
• 关键词: phase-change materials; memory

摘要

Glasses are commonly described as disordered counterparts of the corresponding crystals; both usually share the same short -range order, but glasses lack long -range order. Here, a quantification of chemical bonding in a series of glasses and their corresponding crystals is performed, employing two quantum- chemical bonding descriptors, the number of electrons transferred and shared between adjacent atoms. For popular glasses like SiO2, GeSe2, and GeSe, the quantum- chemical bonding descriptors of the glass and the corresponding crystal hardly differ. This explains why these glasses possess a similar short -range order as their crystals. Unconventional glasses, which differ significantly in their short -range order and optical properties from the corresponding crystals are only found in a distinct region of the map spanned by the two bonding descriptors. This region contains crystals of GeTe, Sb2Te3, and GeSb2Te4, which employ metavalent bonding. Hence, unconventional glasses are only obtained for solids, whose crystals employ theses peculiar bonds.