[en] 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.
Disciplines :
Physics Chemistry
Author, co-author :
Raty, Jean-Yves ; Université de Liège - ULiège > Département de chimie (sciences)
Bichara, Christophe; Centre Interdisciplinaire de Nanoscience de Marseille, Aix-Marseille University, CNRS UMR 7325, 13288 Marseille, France
Schön, Carl-Friedrich; Institute of Physics 1A, Rheinisch-Westfälische Technische Hochschule Aachen University, 52074 Aachen, Germany
Gatti, Carlo ; Consiglio Nazionale delle Ricerche - Istituto di Scienze e Tecnologie Chimiche "Giulio Natta", Milano 20133, Italy ; Istituto Lombardo Accademia di Scienze e Lettere, Milano 20121, Italy