Abstract Shape and size of YF3 particles are determinant in hydrothermal synthesis experiments, whereas the surfaces’ structural and thermodynamic parameters are largely unknown but are indispensable for further optimizations to the YF3 micro- and nanocrystals. In this work we focus on {020}, {111}, { 10 1 ¯ } and { 1 ¯ 02 } facets that are frequently observed. For each orientation, structures and surface energies are obtained using density functional theory calculations. The surface energies are found to be in the order of { 020 } { 111 } { 10 1 ¯ } { 1 ¯ 02 } . The Wulff shape is truncated octahedron, and may expose { 1 ¯ 02 } facets under fluorine-lean conditions. For other experimentally observed shapes (octahedron and diamond-like polyhedron), we present necessary modifications to the surface energies through the inverse Wulff construction method. The results are expected to be helpful in choosing surface-specific surfactants in synthesizing YF3 crystals with targeted morphologies.

中文翻译：

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YF3 形貌和表面的热力学稳定性建模

摘要 YF3 颗粒的形状和尺寸是水热合成实验中的决定因素，而表面的结构和热力学参数在很大程度上是未知的，但对于 YF3 微晶和纳米晶的进一步优化是必不可少的。在这项工作中，我们专注于经常观察到的 {020}、{111}、{10 1¯} 和 {1¯02} 方面。对于每个方向，使用密度泛函理论计算获得结构和表面能。发现表面能的顺序是{020}{111}{101¯}{1¯02}。Wulff 形状是截断的八面体，在贫氟条件下可能会暴露 { 1¯ 02 } 面。对于其他实验观察到的形状（八面体和类金刚石多面体），我们通过逆 Wulff 构造方法对表面能进行了必要的修改。预计该结果有助于选择表面特异性表面活性剂以合成具有目标形态的 YF3 晶体。