Mixed-alkali glasses

Day, D.E. (1976). Mixed alkali glasses - their properties and uses. Journal of... 

Fig. 4.1 Arrhenius plots for ionic conductivity, (a) General behaviour for ionically conducting glasses. At room temperature, the most conductive (Li or Ag ) have the lowest activation energy. For the less conductive glasses (Cs or mixed alkali glasses) the activation energy is around 1 eV. (b) Experimental data for Li conducting glasses (Souquet and Kone, 1986).

Cation Distributions in Mixed-Alkali Glasses Studied by Wa Spin Echo... 

Table 6.2 Summary of properties for mixed alkali glasses (After Day, 1976).

FWHM and A is the value of A v corresponding to the rigid lattice - low temperature) and found that the Li jump frequency does decrease much the same way as in mixed alkali glasses. 

Ngai and Jain (1986) investigated the a.c. electrical conductivity (discussed in chapter 7) of mixed isotope and mixed alkali glasses and... 

It was also found that the variations of l/Ti required a Davidson-Cole distribution function for best fit. In the mixed alkali glasses the MT plots at high temperatures become symmetrical and broader. The activation energies determined from NMR, Enmr, and the E from conductivity measurements have also been compared. Since Li NMR senses only the lithium ion and not the other alkali, the Enmr in mixed alkali regions Eire observed to be lower than Ea. 

Vessal, B., Greaves, G. N., Martin, P. T., Chadwick, A. V., Mole, R. and Houde-Walter, S. (1992) Cation Microsegregation and Ionic Mobility in Mixed Alkali Glasses, Nature, 356, 504-506. 

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