本研究利用固態熔融反應搭配助熔長晶法，成功地合成出新穎硫族化合物K1.51(8)Zn0.74(8)In4.60(6)S8.00 (1)，其空間群及晶系為Trigonal R3，單位晶格軸長分別為a = 3.8442(7) Å, b = 3.8442(7) Å, c = 62.300(11) Å。此層狀化合物之結構是由InS6八面體與MS4 (M = Zn、In)四面體以共用角的形式形成兩種不同的厚層，層和層之間再以陽離子K+ 填充在骨架孔道當中維持電荷平衡。
此化合物之純相合成是藉由單晶數據所得之理論分子式比例做調整，經由高溫800°C反應確保起始物完全熔融，接著在600°C進行退火(annealing)程序，產物為黃色六角形薄片狀晶體。在顯微鏡下挑選定量晶體並以差示熱分析儀鑑定，發現此化合物具有良好之熱穩定性，沒有裂解行為產生。透過紫外光-可見光-近紅外光吸收光譜儀並利用Kubelka-Munk equation計算出此化合物能隙為2.45 eV，和商業常見之非線性光學材料AgGaS2 (band gap = 2.64 eV)相接近。期許在光學測量上擁有良好的表現，使其成為具有高利用價值的非線性光學材料。

A novel metal chalcogenide K1.51(8)Zn0.74(8)In4.6(6)S8.00 (1) with a non-centrosymmetric framework was successfully synthesized by solid state reaction using a KBr flux. The crystal crystallizes in the space group trigonal R3 with a = 3.8442(7) Å, c = 62.300(11) Å, V = 797.3(4) Å3 and Z = 3. The structure adopts a new two-dimensional structure, which linkage motifs can be divided into two distinct of layers parallel to the ab plane: one layer is formed by In(1)S6 octahedral and the M(2)S4 (M = Zn, In) tetrahedra, the other is formed by In(4)S6 octahedral and the M(3)S4 (M = Zn, In) tetrahedra. The K+ cations are distributed between the layers to keep the charge neutralization.
The major phase of compound is synthesized using the stochiometric ratio in the reaction heated at 800°C, followed by an annealing procedure at 600°C, and finally cooled to room temperature by turning off the furnace. A large amount of plate and yellow crystals were observed in the product. The crystals were collected for the measurements of thermal stability, which result showed a high melting point undetectable until 900°C. UV-visible-near-infrared absorption spectrum analyzed by the Kubelka-Munk equation shows the compound featuring energy gap of 2.45 eV, which is comparable the commercial nonlinear optical material of AgGaS2 (band gap = 2.64 eV).

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