Supporting Information - "Identifying Potential BO2 Oxide Polymorphs for Epitaxial Growth Candidates"

Abstract: ======= Transition metal dioxides (BO2) exhibit a number of polymorphic structures with distinct properties, but the isolation of different polymorphs for a given composition is carried out using trial and error experimentation. We present computational studies of the relative stabilities and equations of state for six polymorphs (anatase, brookite, rutile, columbite, pyrite, and fluorite) of five different BO2 dioxides (B = Ti, V, Ru, Ir, and Sn). These properties were computed in a consistent fashion using several exchange correlation functionals within the density functional theory formalism, and the effects of the different functionals are discussed relative to their impact on predictive synthesis. We compare the computational results to prior observations of high-pressure synthesis and epitaxial film growth and then use this discussion to predict new accessible polymorphs in the context of epitaxial stabilization using isostructural substrates. For example, the relative stabilities of the columbite polymorph for VO2 and RuO2 are similar to those of TiO2 and SnO2, the latter two of which have been previously stabilized as epitaxial films. On Figshare ========== Data has been stored as a JSON file and contains information about how every calculation was setup, like the planewave cutoff, exchange correlation functional, <em>k</em>-point grid, etc. It also contains relevant output from the calculation, like total energies, volumes, unit cell parameters, atomic positions, forces, etc. Supporting images are included in a zipped folder. Full Article ======== http://pubs.acs.org/doi/abs/10.1021/am4059149 Documented supporting Info ====================== http://pubs.acs.org/doi/suppl/10.1021/am4059149/suppl_file/am4059149_si_001.pdf

摘要：======= 过渡金属二氧化物（transition metal dioxides，通式记为BO₂）存在多种具有独特性质的多晶型结构，但针对特定组分分离不同多晶型仍需依赖试错式实验手段。我们针对五种不同的BO₂型二氧化物（B元素分别为Ti、V、Ru、Ir、Sn）的六种多晶型（锐钛矿、板钛矿、金红石、铌铁矿型、黄铁矿型及萤石型）开展了相对稳定性与状态方程的计算研究。本研究采用密度泛函理论（density functional theory, DFT）框架下的多种交换关联泛函（exchange correlation functional），以统一的计算流程求解上述性质，并讨论了不同泛函对预测性合成的影响。我们将计算结果与已报道的高压合成及外延薄膜生长实验结果进行对比，并以此为基础，针对采用同结构衬底实现外延稳定化的场景，预测了可获取的新型多晶型。例如，VO₂与RuO₂的铌铁矿型多晶型相对稳定性与TiO₂和SnO₂相近，而后两者此前已被成功制备为外延薄膜。
在Figshare平台上：========== 本数据集以JSON格式存储，包含所有计算的配置信息，例如平面波截断能、交换关联泛函、k点网格等。同时数据集还包含计算的相关输出结果，例如总能量、晶胞体积、晶胞参数、原子位置、受力等。辅助图像文件已打包至压缩文件夹中。
完整论文 ======== http://pubs.acs.org/doi/abs/10.1021/am4059149
存档的补充材料 ====================== http://pubs.acs.org/doi/suppl/10.1021/am4059149/suppl_file/am4059149_si_001.pdf