The exploration of the appropriate red phosphor with good luminescence properties is an important issue in the development of current white light-emitting diode(WLED) devices. Transition metal Mn-doped compounds are f...The exploration of the appropriate red phosphor with good luminescence properties is an important issue in the development of current white light-emitting diode(WLED) devices. Transition metal Mn-doped compounds are fascinating luminescent materials. Herein, we performed a systematic theoretical study of the microstructure and optical properties of K_2TiF_6:Mn^(4+) using the CALYPSO structure search method in combination with first-principles calculations. We uncovered a novel structure of K_2TiF_6:Mn^(4+) with space group P-3m1 symmetry, where the impurity Mn_(4+) ions are accurately located at the center of the MnF_6 octahedra. Based on our developed complete energy matrix diagonalization(CEMD)method, we calculated transition lines for ~2E_g →~4A_2,~4A_2→~4T_2, and^4A_2→T2at 642 nm, 471 nm, and 352 nm,respectively, which are in good agreement with the available experimental data. More remarkably, we also found another transition(~4A_2→~2T_2) that lies at 380 nm, which should be a promising candidate for laser action.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.11574220)Fundamental Research Funds for the Central Universities,China(Grant No.SWU118055)+1 种基金the Special Program for Applied Research on Super Computation of the NSFC-Guangdong Joint Fund(the second phase)China
文摘The exploration of the appropriate red phosphor with good luminescence properties is an important issue in the development of current white light-emitting diode(WLED) devices. Transition metal Mn-doped compounds are fascinating luminescent materials. Herein, we performed a systematic theoretical study of the microstructure and optical properties of K_2TiF_6:Mn^(4+) using the CALYPSO structure search method in combination with first-principles calculations. We uncovered a novel structure of K_2TiF_6:Mn^(4+) with space group P-3m1 symmetry, where the impurity Mn_(4+) ions are accurately located at the center of the MnF_6 octahedra. Based on our developed complete energy matrix diagonalization(CEMD)method, we calculated transition lines for ~2E_g →~4A_2,~4A_2→~4T_2, and^4A_2→T2at 642 nm, 471 nm, and 352 nm,respectively, which are in good agreement with the available experimental data. More remarkably, we also found another transition(~4A_2→~2T_2) that lies at 380 nm, which should be a promising candidate for laser action.
