Infrared Absorption of Antimonate Glass

Abstract

It was confirmed that the area of the glass forming region of the system Sb₂O₃-Al₂O₃-R₂O (Na₂O+K₂O) increases with the addition of SiO₂ or GeO₂.
The glasses containing 5% SiO₂ or GeO₂ melted under oxidizing condition (o. glass) gave a different infrared transmission from those melted under neutral condition (n. glass). Also the difference in such properties as the color, density, softening point, and density were observed.
O. glass has better infrared transmittance and chemical durability than n. glass which gave broad absorption band between 750 and 1000cm^-1 and 1520cm^-1. These two absorption bands at 1420cm^-1, and sharp absorption bands at 1420 and 1520cm^-1. These absorption bands at 1420 and 1520cm^-1 appeared when o. glass is devitrified.
AlSbO₄ crystal has the absorption band at 1420cm^-1. After heating with Na₂O the crystal gave a broad absorption band between 750 and 1000cm^-1.
It was, therefore, concluded that n. glass contains the crystallite region, and the chain segments composed of Al³⁺Sb⁵⁺O tetrahedra are built up more easily in o. glass than in n. glass; also it may be assumed that SiO₂ or GeO₂ bridges the chain segment of AlSbO₄ tetrahedra.