Ingram Malcolm D, Pas Steven J, Cramer Cornelia, Gao Yong, Hill Anita J
Department of Chemistry, University of Aberdeen, Meston Walk, Aberdeen, Scotland, UK AB24 3UE.
Phys Chem Chem Phys. 2005 Apr 21;7(8):1620-3. doi: 10.1039/b419201j.
PALS experiments reveal a minimum in ortho-positronium (o-Ps) lifetimes and a maximum in the corresponding intensities that emerge when mixed-cation (Li/Na) borate glasses are heated from ambient temperatures up to 473 K. These free volume 'anomalies' appear to be a true manifestation of the mixed alkali effect (MAE). They are consistent with a mechanism of ion transport involving cooperation between hops of unlike cations, resulting in increased disturbance of the glass network. The result lends support to the dynamic structure model.
正电子湮没寿命谱（PALS）实验表明，当混合阳离子（Li/Na）硼酸盐玻璃从室温加热到473K时，仲正电子素（o-Ps）寿命出现最小值，相应强度出现最大值。这些自由体积“异常”似乎是混合碱效应（MAE）的真实表现。它们与一种离子传输机制一致，该机制涉及不同阳离子跳跃之间的协同作用，导致玻璃网络的干扰增加。这一结果支持了动态结构模型。
