Crystal Growth, Structural Characterization, and Linear Thermal Evolution of KGd(PO3)4

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• 作者：I. Parreu ; R. Solé ; Jna. Gavaldà ; J. Massons ; F. Dí ; az ; and M. Aguil&oacute
• 刊名：Chemistry of Materials
• 出版年：2005
• 出版时间：February 22, 2005
• 年：2005
• 卷：17
• 期：4
• 页码：822 - 828
• 全文大小：291K
• 年卷期：v.17,no.4(February 22, 2005)
• ISSN：1520-5002

文摘

We determined the crystallization region of KGd(PO₃)₄ (KGP) in the ternary system Gd₂O₃-K₂O-P₂O₅, the isotherms of saturation temperature and six neighboring phases: KPO₃, GdPO₄, KGdP₄O₁₂,Gd(PO₃)₃-orthorhombic, Gd(PO₃)₃-monoclinic, and GdP₅O₁₄. We successfully grew KGP single crystalsby the top-seeded solution growth (TSSG) slow cooling method. To optimize the growth process andobtain high-quality KGP crystals, solution composition and seed orientation were analyzed and a growthdevice was added. KGP is isostructural to KNd(PO₃)₄, crystallizes in the monoclinic system P2₁ and thecell parameters determined are a = 7.2701(11), b = 8.3818(8), and c = 7.9608(10) Å, mages/gifchars/beta2.gif" BORDER=0 ALIGN="middle"> = 91.776(12)mages/entities/deg.gif">,Z = 2, and V = 484.87(11) ų. We studied how they evolved as the temperature increased from roomtemperature to 773 K and observed an almost isotropic linear thermal expansion, the tensor of which wealso calculated. In the room temperature to 1273 K range analyzed, we found that KGP irreversiblydecomposed at 1142 K. The second harmonic efficiency, qualitatively measured by the Kurtz method,was at least similar to that of KH₂PO₄ (KDP).