Highly transparent KAlF₄ and Na₅Al₃F₁₄ fluoride bulk single crystals in size of ≈Ф 50 mm × 10 mm are successfully grown for the first time by a modified Bridgman method. The physicochemical properties of the single crystals are investigated with the help of X-ray diffraction (XRD), thermogravimetric and differential thermal analysis (TG-DTA), absorption spectrum, Fourier infrared spectroscopy, and Raman spectrum measurements. The KAlF₄ and Na₅Al₃F₁₄ phases of the obtained single crystals are determined from the results of XRD. The melting points of KAlF₄ and Na₅Al₃F₁₄ are measured to be ≈549 and ≈705 ℃ from their DTA curves. The maximum matrix phonon energies of KAlF₄ and Na₅Al₃F₁₄ single crystals are 544 and 530 cm^–1 from their Raman spectra. The KAlF₄ single crystal shows high transmittance from 2000 to 5500 nm, while Na₅Al₃F₁₄ from 950 to 6000 nm. The energy gaps of KAlF₄ and Na₅Al₃F₁₄ are calculated to be 5.34 and 5.94 eV based on transmission spectra, respectively.

中文翻译：

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Bridgman 法生长 KAlF4 和 Na5Al3F14 氟化铝单晶

首次通过改进的Bridgman方法成功生长出尺寸为≈Ф50 mm×10 mm的高透明KAlF ₄和Na ₅ Al ₃ F ₁₄氟化物块状单晶。借助 X 射线衍射 (XRD)、热重和差热分析 (TG-DTA)、吸收光谱、傅里叶红外光谱和拉曼光谱测量，研究了单晶的物理化学性质。所得单晶的KAlF ₄相和Na ₅ Al ₃ F ₁₄相由XRD的结果确定。_{KAlF 4}和 Na ₅的熔点从它们的 DTA 曲线测得Al ₃ F ₁₄分别为 ≈549 和 ≈705 ℃。_{KAlF 4}和 Na ₅ Al ₃ F ₁₄单晶的最大基体声子能量从它们的拉曼光谱分别为 544 和 530 cm ^{-1 。}KAlF ₄单晶在 2000 至 5500 nm 范围内显示出高透射率，而 Na ₅ Al ₃ F ₁₄在 950 至 6000 nm 范围内显示出高透射率。基于透射光谱计算出KAlF ₄和Na ₅ Al ₃ F _{14的能隙分别为5.34和5.94 eV。}