Ab Initio Thermodynamics and Kinetics for Coalescence of Two-Dimensional Nanoislands and Nanopits on Metal (100) Surfaces
Ab Initio Thermodynamics and Kinetics for Coalescence of Two-Dimensional Nanoislands and Nanopits on Metal (100) Surfaces
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DOI：
10.1021/acs.jpcc.6b07328
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发表时间：
2016-09
影响因子：
3.7
通讯作者：
Yong Han;C. Stoldt;P. Thiel;J. Evans
中科院分区：
文献类型：
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作者：
Yong Han;C. Stoldt;P. Thiel;J. Evans
未重构金属（100）表面上的成对的低应变二维纳米岛和纳米孔的沉积后聚结或烧结通常由沿沿着台阶边缘的扩散介导，并且对相关动力学高度敏感。因此，对于选定的系统，我们提供了一个从头算密度泛函理论（DFT）水平的系统热力学和动力学的描述。具体而言，我们评估横向对和三人组的相互作用都常规与吸附原子在4倍的中空吸附网站，和非常规与一个吸附原子在桥位过渡态跳跃。而不是使用标准的集群扩展算法，这些相互作用的确定受到的约束，关键的阶跃边缘属性被准确地恢复。总之，这两类相互作用决定的障碍，边缘扩散过程中的任何地方的步骤配置，包括扩散沿着紧密包装的110毫米边缘，扭结圆化，曲折的过程中，在扭结100毫米的步骤，和提取…
Postdeposition coalescence or sintering of pairs of low-strain two-dimensional nanoislands and nanopits on unreconstructed metal (100) surfaces is typically mediated by diffusion along step edges, and is highly sensitive to the associated kinetics. Thus, for selected systems, we provide an ab initio density functional theory (DFT) level description of both system thermodynamics and kinetics. Specifically, we assess lateral pair and trio interactions both conventionally with adatoms at 4-fold hollow adsorption sites, and unconventionally with one adatom at the bridge-site transition state for hopping. Rather than use standard cluster expansion algorithms, these interactions are determined subject to the constraint that key step-edge properties are recovered exactly. Together, both classes of interactions determine barriers for edge diffusion processes for any local step configuration, including diffusion along close-packed ⟨110⟩ edges, kink rounding, meandering processes at kinked ⟨100⟩ steps, and extracti...