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Glass of the Na 2 O -B 2 O 3 -SiO 2 system with a B 2 O 3 content from 20 to 40% was investigated by high-temperature Raman spectroscopy. It was shown that when the boron oxide content was gradually increased, the silicate network undergoes depolymerization, which is confirmed by the change in the ratio of the intensities of the bands characteristic of tetrahedrons with a different number of nonbridge oxygen atoms (Q 2 and Q 3 ). The borate constituent has BO 4 tetrahedrons which then alternate with nonsymmetrical BO 3 triangles with nonbridge oxygen atoms.Three-component silicate systems that contain another oxide in addition to silicon dioxide -a glass former -are of great interest both from a scientific and a manufacturing point of view. The borosilicate system is one of the most important, and studying it is of enormous importance, particularly for developing glass for different applications and matrices for burial of radioactive wastes. We know [1] that the properties of these matrices are determined to a significant degree by the coordination and structural position of boron in borosilicate glasses. Obtaining information on the structure of the glasses is not only necessary for understanding the nature of the glass state, but also for directed synthesis of materials with defined properties.Borosilicate glasses are systems with two cationic glass formers, each of which can form its own anion groups in reacting with alkali metal oxides. The features of formation of borate and silicate constituents and their reaction determine the basic structural features and physicochemical properties of borosilicate glasses and melts. In addition, the properties of borosilicate glasses are a function of the structural state of the boron in the system, which can change its coordination number from three to four as a function of the composition. Varying the concentration of boron in the glasses and changing its coordination allows controlling their properties within wide limits, which is of interest with respect to using them as promising materials in radiation materials science.Three-component glasses of the Na 2 O -B 2 O 3 -SiO 2 system were synthesized from analytically pure amorphous SiO 2 , very pure boron trioxide, and cp carbonate Na 2 CO 3 . Samples of sodium borosilicate glasses with a Na 2 O : B 2 O 3 ratio equal to one and a different SiO 2 content were investigated (Fig. 1). The batch was carefully mixed in a mortar with alcohol, dried, and melted in a platinum crucible in a Silit furnace at a temperature below 1473 K until the melt was totally homogenized and then air hardened.The structure of the borosilicate glasses as a function of the composition (Na 2 O -B 2 O 3 -SiO 2 system with a mass content of B 2 O 3 of 20 to 40% 3 ) was investigated by Raman spectroscopy. A Labram iHR 320 spectrometer with an Olympus BX41 microscope was used for recording the Fig. 1. Composition diagram of the Na 2 O -B 2 O 3 -SiO 2 threecomponent system (the numbers of the compositions of the synthesized glasses are designated by the...

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