本篇研究使用助熔長晶法，成功的合成出新穎硫族化合物K1.33Zn1.33-3xIn4-2xS8，其對稱性空間群為Trigonal R3m，單位晶格長為a=b=3.8439(3)Å，c=62.280(9)Å。本篇論文在層狀ZnmIn2S3+m系統中插入K陽離子，插入K+後會改變ZnmIn2S3+m系統中以往的結構，像是ZnIn2S4為以層中間一八面體兩側各延伸出一四面體形成三鏈為一層的結構，Zn2In2S5為層中間一八面體兩側分別為一四面體跟兩個四面體組成四鏈為一層的結構。但插入K+後改變了該系統的層狀規律，將不再是以八面體為中心向兩側延伸四面體的結構，而是一層由InS6八面體跟MS4 (M=Zn/In) 四面體組成形成兩鏈為一層的結構，而一個unit cell中，由六個層延c軸排列所組成，每層由InS6八面體跟MS4 (M=Zn/In) 四面體以共角形式連接，形成兩種類型的層，上述六個層由這兩種類型的層重複排列而成。而層與層之間具有K+陽離子插入，以維持整體結構的電荷平衡。且有文獻表示具有極性的化合物會具有鐵電性質1以及二次諧波產生，因此本篇研究也對上述兩種性質進行量測，發現該材料具有不錯的二倍頻訊號，但並沒有鐵電性質，不過目前發現它具有微弱的壓電性質。

In this work, a novel layered metal chalcogenide K1.33Zn1.33-3xIn4-2xS8 was synthesized by solid-state reaction. This structure crystallizes in a non-centrosymmetric space group of Trigonal R3m with cell parameters a = 3.8439(3) Å, c=62.280(9) Å. We successfully inserted K cations into the layered ZnmIn2S3+m (m=1~5) system. After insertion of K cations, the layered structure of the ZnmIn2S3+m system will change, and no longer have an octahedral as the center and grow tetrahedra along the sides. The structure of this layered compound is composed of InS6 octahedral and MS4 (M=Zn/In) tetrahedra connected in the form of corner sharing, and K cation insertion between the layers. According to crystallography, we had known that polar compounds have a second harmonic generator respond and may have ferroelectric properties. Our compound is non-centrosymmetric structure, so it may have both properties. However, according to the measurement results, we found that the compound does not have ferroelectric properties, but has weak piezoelectric properties.

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