First-Principles study for the influence of ion vacancies on the doped Cr3+and transition dipole moment in anti-perovskite structure La3(SiN2O2)N

Typically, the luminescence properties of doped luminescent centers, such as rare earth ions or transition metal ions, are significantly influenced by the properties of the luminescent host materials. In this study, we focus on how the electronic band structure and transitions between the valence band maximum (VBM) and conduction band minimum (CBM) are affected by the formation of individual V La or VSi, as well as the coexistence of V La with V Si in La3(SiN2O2)N. The doped Cr3+ as luminescent centers preferentially substitutes for Si4+ rather than La3+. The band gap characteristics of La3(SiN2O2)N, associated with its absorption properties, can be modified by the presence of ion vacancies and doped Cr3+. Additionally, the computed transition dipole moment of La3(SiN2O2) N: VSi, Cr3+ is the highest. This indicates the maximal transition between VBM and CBM, resulting in the most robust charge transfer from the p orbital of N 3- to the d orbital of Cr3+.Enhanced charge transfer can also result in effective luminescence. Therefore, it can be concluded that La3(SiN2O2)N with individual V Si is suitable as a luminescent host material for Cr3+ doping. The study of La3(SiN2O2)N with different ion vacancies and Cr3+ doping provides information for the development of new luminescent materials that exhibit strong luminescence.