Mn⁴⁺‐doped fluoride phosphors have been widely used in wide‐gamut backlighting devices because of their extremely narrow emission band. Solid solutions of Na₂(Si_xGe_1−x)F₆:Mn⁴⁺ and Na₂(Ge_yTi_1−y)F₆:Mn⁴⁺ were successfully synthesized to elucidate the behavior of the zero‐phonon line (ZPL) in different structures. The ratio between ZPL and the highest emission intensity υ₆ phonon sideband exhibits a strong relationship with luminescent decay rate. First‐principles calculations are conducted to model the variation in the structural and electronic properties of the prepared solid solutions as a function of the composition. To compensate for the limitations of the Rietveld refinement, electron paramagnetic resonance and high‐resolution steady‐state emission spectra are used to confirm the diverse local environment for Mn⁴⁺ in the structure. Finally, the spectral luminous efficacy of radiation (LER) is used to reveal the important role of ZPL in practical applications.

中文翻译：

---

通过调节Mn4 +激活的窄带氟化物荧光粉的晶体对称性和局部结构来控制发光。

掺杂Mn ^4+的氟化物磷光体因其极窄的发射带而被广泛用于宽色域背光设备中。已成功合成了Na ₂（Si _x Ge _{1- x}）F ₆：Mn ⁴⁺和Na ₂（Ge _y Ti _1-y）F ₆：Mn ^4+的固溶体，以阐明零声子线的行为（ ZPL）。ZPL和最高发射强度之间的比率υ ₆声子边带与发光衰减率有很强的关系。进行第一性原理计算以模拟所制备的固溶体的结构和电子性质随组成的变化。为了弥补Rietveld改进的局限性，电子顺磁共振和高分辨率稳态发射光谱被用于确认结构中Mn ⁴⁺的不同局部环境。最后，辐射的光谱发光效率（LER）用于揭示ZPL在实际应用中的重要作用。