Connectivity of glass structure. Oxygen number

International Conference on Mechanical Engineering, Automation and Control Systems 2017

机械制造;无线电电子学;计算机科学

Medvedev, E.F.^1 ; Min'Ko, N.I.^2

Federal State Unitary Enterprise Russian Federal Nuclear Center, All-Russian Research Institute of Experimental Physics, 37 Mira Av., Sarov, Nizhny Novgorod reg.

607188, Russia^1

Belgorod State Technological University Named after V.G. Shukhov, 46 Kostyukov St., Belgorod

308012, Russia^2

关键词: Chemical technologies;    Connectivity factor;    Connectivity function;    Degree of connectivity;    Functional dependence;    Mathematical expressions;    Multicomponent glass;    Structure connectivities;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/327/3/032038/pdf
DOI  :  10.1088/1757-899X/327/3/032038

学科分类：计算机科学（综合）

来源: IOP

【 摘 要 】

With reference to mathematics, crystal chemistry and chemical technology of synthesis of glass structures in the solution (sol-gel technology), the paper is devoted to the study of the degree of connectivity of a silicon-oxygen backbone (fSi) and the oxygen number (R) [1]. It reveals logical contradictions and uncertainty of mathematical expressions of parameters, since fSiis not similar to the oxygen number. The connectivity of any structure is a result of various types of bonds: ion-covalent, donor-acceptor, hydrogen bonds, etc. Besides, alongside with SiO2, many glass compositions contain other glass-forming elements due to tetrahedral sites thus formed. The connectivity function of a glassy network with any set of glass-forming elements is roughly ensured by connectivity factor Y [2], which has monovalent elements loosening a glassy network. The paper considers the existence of various structural motives in hydrogen-impermeable glasses containing B2O3, Al2O3, PbO, Na2O, K2O and rare-earth elements. Hence, it also describes gradual nucleation, change of crystal forms, and structure consolidation in the process of substance intake from a matrix solution according to sol-gel technology. The crystal form varied from two-dimensional plates to three-dimensional and dendritical ones [3]. Alternative parameters, such as the oxygen number (O) and the structure connectivity factor (Y), were suggested. Functional dependence of Y=f(O) to forecast the generated structures was obtained for two- and multicomponent glass compositions.