Structure of high-alkali melts in the lithium borate system from vibrational spectroscopic data

Melts of the compositions Li 2 O · B 2 O 3 , 3Li 2 O · 2B 2 O 3 , 2Li 2 O · B 2 O 3 , and 3Li 2 O · B 2 O 3 (asbatched) are investigated using high-temperature Raman spectroscopy in the temperature range 973–1373 K. The IR and Raman spectra of polycrystalline samples of the corresponding compositions are measured. The Raman spectra of the melts and the products of their crystallization are compared, and the frequencies of characteristic vibrations of the structural units are determined. The regularities of the changes in the structure of the melts are established as a function of the composition and temperature.