Collaborative Research: Investigation of Anion Incompatibility in the Ca10(PO4)6(OH,F,Cl)2 Apatite Atomic Arrangement

合作研究：Ca10(PO4)6(OH,F,Cl)2 磷灰石原子排列中阴离子不相容性的研究

• 批准号: 1249696
• 负责人: Hanna Nekvasil
• 金额: $ 32.7万
• 依托单位: SUNY at Stony Brook
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-05-01 至 2018-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1249696&HistoricalAwards=false
• 关键词: Collaborative; Research; Investigation; Anion; Incompatibility

Apatite, Ca10(PO4)6(OH,F,Cl)2, is the tenth most abundant mineral on Earth and one with fundamental importance in geology, materials science, medicine, dentistry, pollutant mitigation, and as the foundation of the Earth's phosphorus cycle; indeed, all hard tissue of the human body except small parts of the inner ear are made of apatite. All of these applications of apatite require understanding of the atomic arrangement of the mineral. Despite the extensive multidisciplinary literature on apatite crystal chemistry, the atomic arrangements of members of the (OH,F,Cl) binary and ternary systems are not well understood and our current knowledge is full of inconsistencies that must be resolved; apatite is one of the rare minerals for which the atomic arrangement of the solid solutions cannot be predicted from the end-member arrangements.Mixing of the end-member atomic arrangements suggests, for example, that binary members of the system must undergo symmetry breaking, possess immiscibility gaps, incorporate essential vacancies with an unknown method of charge balance, and/or possess anion positions that are not currently recognized. This multi-faceted proposed study will couple mineral synthesis and detailed compositional characterization with single-crystal X-ray structure analysis and Magic-Angle-Spinning Nuclear Magnetic Resonance spectroscopic studies in order to elucidate the nature of solid solution among and between the OH, F, Cl ternary apatites, and provide a better fundamental understanding of anionic substitution and phase behavior. The results of this study will have applications in the fields of geology, materials science, medicine, and dentistry. A proof-of-concept study demonstrates that miscibility along the F-Cl join is achieved by the creation of at least four anion sites in the F-Cl anion column, and confirms the efficacy of the proposed synthesis and analysis methods.

磷灰石，Ca 10（PO 4）6（OH，F，Cl）2，是地球上第十大最丰富的矿物质，在地质学、材料科学、医学、牙科、污染物缓解和地球磷循环的基础上具有根本的重要性;事实上，除了内耳的一小部分之外，人体的所有硬组织都由磷灰石组成。磷灰石的所有这些应用都需要了解矿物的原子排列，尽管有大量关于磷灰石晶体化学的多学科文献，但对（OH，F，Cl）二元和三元体系成员的原子排列还没有很好的了解，我们目前的知识充满了必须解决的不一致性;磷灰石是一种罕见的矿物，其固溶体的原子排列不能从端元排列预测。端元原子排列的混合表明，例如，该系统的二元成员必须经历对称性破缺，具有不可吸收的间隙，以未知的电荷平衡方法引入必要的空位，和/或具有目前未被识别的阴离子位置。这个多方面的建议研究将耦合矿物合成和详细的成分表征与单晶X射线结构分析和魔角旋转核磁共振光谱研究，以阐明之间的OH，F，Cl三元磷灰石固溶体的性质，并提供一个更好的基本了解阴离子取代和相行为。这项研究的结果将在地质学，材料科学，医学和牙科领域的应用。 概念验证研究表明，通过在F-Cl阴离子柱中产生至少四个阴离子位点，实现了沿F-Cl连接沿着的可吸收性，并证实了所提出的合成和分析方法的有效性。