Densities and surface tensions of lithium niobate melts

Abstract

The density and surface tension have been measured in lithium niobate melts of different compositions with Li 2O content varying from 47 to 50 mol% in the temperature range 1510–1630 K. The densities and surface tensions of the melts in the composition range decrease linearly with the increase of temperature, while an increase in Li 2O content causes the density to decrease and surface tension to increase. The temperature coefficient of the densities and the surface tensions are also given for different compositions, which have a minimum and a maximum value of the densities and surface tensions at congruent compositions. The time dependence of the densities of the melts shows that the melt at the congruent composition is more homogeneous and that the stoichiometrical melt should be aged for 3 h to get a stable density value.