本論文以高溫高壓水熱合成法在460°C和600 bar的條件下合成兩個新穎的碳硼酸鹽，Ba3[B6O10(OH)2](CO3) (A1) 和 Ba6[B12O21(OH)2](CO3)2 (A2)。藉由單晶X光繞射儀，解析出化合物的晶體結構，輔以粉末X光繞射圖與理論圖比對，確定樣品純度以供後續分析。另外透過紅外線光譜、熱重分析、固態核磁共振等方式進行定性及光學性質的分析。 化合物A1、A2的基礎建構單元用Burns 研究團隊所提出的“基本結構建築單元”(fundamental building blocks, FBBs) 的概念都可寫成24:<2>=<4>=<2>。其中A1建構單元為椅式結構，A2則是同時包含椅式結構與船型結構。A1為非中心對稱的透明塊狀晶體，結構為二維的層狀結構，其中鋇離子與碳酸根坐落在層間。經由光學性質測量，證明二次倍頻強度約大於SiO2。A2為中心對稱的透明針柱狀晶體，結構為三維的網狀結構，硼酸鹽骨架形成九員環與十員環的通道，鋇離子和碳酸根就位在通道上。並利用紅外線光譜儀的測量，確認化合物A2結構中有OH基的存在。這兩個化合物因碳酸根獨立存在於硼酸鹽的骨架中而顯得特別，這類型的化合物到目前都是稀有的。 ;Two new barium borate-carbonates, Ba3[B6O10(OH)2]CO3 (A1) and Ba6[B12O21(OH)2](CO3)2 (A2), have been synthesized under high-temperature, high-pressure hydrothermal conditions at 460 °C and 600 bar and characterized by single-crystal and powder X-ray diffraction, IR, TGA, MAS 11B NMR spectroscopy, and second-harmonic generation. The descriptors of the fundamental building blocks (FBB) of both structures are 24:<2>=<4>=<2>. The FBB of A1 has chair conformation and the FBBs of A2 have both chair and boat conformations. A1 adopts a non-centrosymmetric two-dimensional layer structure with the Ba2+ cations and CO32- anions between the layers. Second harmonic generation measurement results confirmed the lack of center of symmetry of the structure. A2 has a centrosymmetric three-dimensional framework structure containing 9- and 10-ring channels with the Ba2+ cations and CO32- anions at the center or on the edges of the channels. The presence of OH group in the structure was confirmed by IR spectroscopy. These two compounds are interesting in terms of the isolated carbonate groups at their own independent sites in the structural channels of the 3D.
