Molecular Structure of Tellurium-Based Optical Glasses and Liquids by Spectroscopy and Calorimetry

利用穆斯堡尔谱、拉曼光谱和量热法研究了两种新型碲基光学玻璃的分子结构。碱土和碱土碲酸盐将与锗合金化，以改变这些非晶态材料的玻璃化转变温度。相应玻璃熔体的易损性将通过粘度、热焓活化能和热膨胀测量确定。结果将与从光谱学中推断出的玻璃分子结构的各个方面相关联。特别令人感兴趣的是探针离子(碘和碲)周围的平均配位。在基本水平上，目前的玻璃提供了便利的系统来进一步探索最近提出的玻璃共价网络中的刚性渗流与相应熔体的脆性之间的关联。在应用层面上，本推力为确定其在光学应用中的可行性提供了基础。

The molecular structure of two new classes of tellurium-based optical glasses will be investigated using Mossbauer spectrosopy, Raman spectroscopy, and calorimetry. The alkaline and alkaline- earth tellurates will be alloyed with germanium to modify the glass transition temperatures of these amorphous materials. The fragility of corresponding glassy melts will be established by viscosity-and enthalpy-activation energies and thermal expansion measurements. The results will be correlated with aspects of glass molecular structure deducted from spectroscopy. Of particular interest is the average coordination around the probe ions (iodine and tellurium). On a basic level, the present glasses provide convenient systems to explore further the recently suggested correlation between rigidity percolation in glassy covalent networks and fragility of corresponding melts. On an applied level, the present thrust provides a basis to determine their viability for optical applications.