Popis: |
An attempt has been made to identify the structural elements in binary lithium, sodium, potassium and cesium silicate melts by voltammetry. In the lithium melts g-SiO2 or quartz-like clusters are proposed, although other interpretations are possible. Further, a second voltammetric wave may be an indication of peroxo bonds in lithium melts. In sodium melts, anions derived from cristobalite have been confirmed by comparison with information from Raman spectra, as have the tridymite derivatives in potassium melts. The structural elements in cesium silicate melts resemble those of potassium. The influence of the alkali ion on the acidity of the melt is calculated and is found to increase in the order Cs < K < Na < Li. |