Structure and function of window glass and Pyrex

Abstract

Window glass is a ternary mixture, while pyrex (after window glass, the most common form of commercial glass) is a quaternary. Building on our previous success in deriving the composition of window glass (sodium calcium silicate) without adjustable parameters, and borrowing from known reconstructed crystalline surfaces, we model pyrex as silica clusters with a specific ternary interface. Our global model explains the thermal expansivity contours of ternary sodium borosilicates, and it is consistent with the optimized resistance of pyrex to mechanical and thermal shocks.It suggests new directions for studying the nanoscopic structure of these remarkable materials.In principle the structure of glasses is an exponentially complex combinatorial problem.In the early days of glass science it was customary to dismiss this problem by saying that network glasses, for example, form "continuous random networks", or that metallic glasses could be modeled by "random" packing of hard spheres. Modern glass theory goes far beyond these early models, but there are still many approaches to understanding glass structure and properties. One approach, that has the advantage of being close to commercial practice, is variational (standard for mathematical studies of non-polynomial complete (complex) problems) and focuses attention on optimizing structural properties as a function of composition. Here we adopt this approach to study pyrex (next to

Modifier cation effects on 29Si nuclear shielding anisotropies in silicate glasses

“…This information is valuable in testing predictive models for structure-property relationships in glasses [96], such as topological constraint theory [97][98][99][100][101] and the related temperature-dependent constraint theory [102,103], where one needs to know enough about the structure of a given glass to identify relevant structural units and constraints; the best source of this kind of structural detail can come from experimental NMR measurements [104][105][106][107].…”

A new transferable interatomic potential for molecular dynamics simulations of borosilicate glasses

“…Borosilicate glasses have various applications, including kitchen and laboratory glassware [1,2], glass fibers [3], chemically strengthened protective cover glasses [4][5][6], glass substrates for high performance displays [7], and nuclear waste immobilization [8][9][10]. Their atomic structure is partially derived from those of pure glassy SiO2 and B2O3 [11].…”

Statistical mechanical model of bonding in mixed modifier glasses

“…Oxide glasses typically consist of multiple network formers and modifiers, creating a vast composition space of possible chemistries. By modifying the glass composition, one can create a highly chemical durable glass like borosilicates, ultra‐high strength aluminosilicate glasses, ultra‐thin display glass, or soda lime glass used for architectural purposes.…”