New oxychloride lead borate glasses in the xPbCl₂–(50-0.5x)PbO–(50-0.5x)B₂O₃ system were synthesized with a maximum lead chloride content of 40 mol%. The characteristic temperatures and mechanical and optical properties were studied. The incorporation of lead chloride led to a significant expansion of the transparency range in the UV (up to 355 nm) and IR regions (up to 4710 nm). Decreases in the Vickers hardness, density, and glass transition temperature were the consequences of a change in the structure. The studied glasses are promising materials for photonics and IR optics. The structure of the PbCl₂–PbO–B₂O₃ system was analyzed in detail using vibrational spectroscopy and X-ray diffraction.

PbCl₂–PbO–SiO₂ glasses doped with Nd³⁺ ions were studied. The photoluminescence intensity, absorption, microhardness, refractive index, and characteristic temperatures of the glasses were measured experimentally. Amorphous structure of the investigated samples was proved by X-ray diffraction (XRD). Energy dispersive X-ray analysis (EDAX) confirmed the incorporation of lead chloride into the glasses. PbCl₂ additions cause decreases in the glass transition, crystallization, and melting temperatures of the lead silicate glasses due to the formation of new structural and chemical units and to significant changes in the glass network. A decrease in microhardness is a consequence of the structural changes. The glasses have high refractive indices in the range of 1.78 to 2.09. The spectral-luminescent properties of the neodymium ions in the PbCl₂-PbO-SiO₂ glasses were investigated in detail for the first time. The absorption spectra show typical Nd³⁺ absorption bands in the visible and infrared spectral regions. The short-wave absorption band lies in the range of 350–380 nm, being shifted to the ultraviolet region by 40 nm relative to the binary PbO-SiO₂ glasses. The synthesized glasses exhibit intense IR photoluminescence, typical for neodymium. The photoluminescence intensity increases with an increase in the lead chloride proportion in the lead silicate oxochloride glasses. The addition PbCl₂ to the lead silicate glasses causes reduction of the maximum phonon energy of the matrix. The decrease in the phonon energy decreases the probability of nonradiative relaxation. The Nd³⁺ ion occurring in a low-energy environment luminesces more efficiently, since the excitation energy is not dissipated via the thermal vibrations of the matrix. The studied glasses are promising materials for the infrared spectral region.