Luminescence Mechanisms for Borate Glasses: The Role of Local Structural Units

摘要: The increasing knowledge of local order and detailed structural information on the neighboring atoms impurity ions or radiation-induced defect states in borate glasses is a powerful argument for more models leading to better understanding luminescence mechanisms, recombination kinetics, other related phenomena. Examples some previous thermoluminescence quenching mechanisms gamma-irradiated aluminoborate doped with Fe are briefly revised. Racah parameters ligand field intensity transition element ion such as Cr3+ found be useful parameters, sensitive nature symmetry distortions, which can controlled by an adequate glass composition design. Fano antiresonances observed optical absorption spectra appear at positions expected from Tanabe–Sugano diagram. spectrum barium Nd3+ merely superposition respective independent absorptions. However, fluorescence appears shifted, thus indicating occurrence energy transfer process excited states, even room temperature. Both excitation chromium neodymium show antiresonance effect but exhibit Lamb shift valleys associated over emission bands Cr3+.