Structure of Densely Packed Oxide Glasses Prepared Using a Levitation Technique
Atsunobu Masuno
Abstract
Many densely packed oxide glasses with no or few network former oxides have recently been synthesized using a levitation technique. They attract attention because of their characteristic glass structures with high packing density, and unusual and exceptional functionalities. The atomic arrangements of the glasses without network former oxides invariably comprise various structural units such as four-, five-, or six-coordinated polyhedra that connect each other with corner-, edge- or face-sharing. Complete fragmentation of regular tetrahedral networks is achieved in glasses with few network former oxides. These are quite different from conventional oxide glasses that consist of regular corner-sharing tetrahedral networks. In densely packed oxide glasses, corner-sharing tetrahedral networks are no longer the most important structural variables for glass formation. In this review, the results of structural investigations for several glasses synthesized by the containerless method using a levitation technique are summarized. The relationship between the glass-forming ability and the atomic arrangements realized in the densely packed oxide glasses is discussed.