Isolated Coordination Polyhedron Confinement in ABP 2 O 7 :Mn 2+ (A = Ba/Sr; B = Mg/Zn).

Many research efforts have focused on designing new inorganic phosphors to meet different application requirements. The structure-photoluminescence relationship between activator ions and the matrix lattice plays an irreparable role in designing target phosphors. Herein, a series of ABP 2 O 7 :Mn 2+ (A = Ba/Sr; B = Mg/Zn) phosphors are prepared for a detailed study on the relationship between the luminescence performance and spatial structure and symmetry of the doping site of Mn 2+ . Due to the weak interaction between nearest B-B pairs, [BO 5 ] is defined as an isolated coordination polyhedron whose structure and symmetry directly influence the photoluminescence of Mn 2+ . The emission wavelength of Mn 2+ is ∼620 nm when it occupies the triangular bipyramid [MgO 5 ] in BaMgP 2 O 7 . When Mn 2+ occupies the quadrangular pyramid-typed [MgO 5 ] or [ZnO 5 ] in SrMgP 2 O 7 , SrZnP 2 O 7 , and BaZnP 2 O 7 , the emission wavelengths peak at ∼670 nm. We propose a conception of isolated coordination polyhedral confinement to clarify the luminescence performance of Mn 2+ in the fivefold coordination configuration with different geometries, which has great theoretical research significance for designing inorganic phosphors.