Li2O-(LiCl)2-B2O3-Al2O3系统玻璃的Raman光谱研究

我们用Raman光谱研究了Li₂O(LiCl)₂B₂O₃-Al₂O₃系玻璃的结构,着重研究了Al₂O₃的影响。对于Li₂O-B₂O₃系玻璃,Li₂O含量增加使玻璃中存在的BO₃三角体转变为BO₄四面体, 关键词：

RAMAN SPECTRA OF GLASSES IN THE Li2O-(LiCl)2-B2O3-Al2O3 SYSTEM

In this paper, the structure of glasses in Li₂O(LiCl)₂B₂O₃-Al₂O₃ system, particularly the influence of Al₂O₃, is investigated by Raman spectra. For Li₂O-B₂O₃ glasses, with increasing Li₂O content, triangular BO₃ units change into BO₄ tetrahedra and borate groups containing more BO₄ are formed. When Li₂O content is greater than 35 mol% the metaborate groups begin to form. By replacing B₂O₃ with Al₂O₃, the Al³⁺ ions introduced in glasses take the four-coordination, and AlO₄ tetrahedra replace BO₄ tetrahedra under the condition of existing sufficient Li₂O. However, when Al₂O₃/Li₂O ratio is close to or even greater than unity, part of Al³⁺ ions are no more in the four-coordination. The experiment also indicates that Raman spectra only depends upon the O/B/Al ratio, showing that the LiCI molecules introduced into the glass are dissociated by glass network. These results can be used to interprete the variations of ionic conductivity with composition.