Towards a transferable design of solid-state embedding models on the example of a rutile TiO2 (110) surface.
Towards a transferable design of solid-state embedding models on the example of a rutile TiO2 (110) surface.
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DOI：
10.1063/1.5125204
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发表时间：
2019-11
期刊：
影响因子：
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通讯作者：
M. Kick;H. Oberhofer
中科院分区：
文献类型：
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作者：
M. Kick;H. Oberhofer
在这项工作中，我们提出了一般的和强大的可转移的原则，在固态嵌入（SSE）的方法，超越了仍然流行的试错法的量子力学处理集群的建设。因此，我们探测质量的不同团簇形状的准确性的小分子的化学吸附能和小极化子形成能在金红石型TiO 2（110）表面作为测试用例。我们的分析表明，至少结合能和电子结构的状态密度的形式往往是相当强大的小，非最佳的集群形状。与此相反，极化子形成的描述可以显着影响所采用的集群几何可能导致错误的能量排序，甚至错误的预测极化状态本身。我们的研究结果表明，这主要是由于边界和周围原子的Hartree势的描述不准确，嵌入环境的补偿不足。这强调了簇的大小和形状对于通用SSE模型的准确性的重要性，这些模型不必针对每个新的化学问题进行改装。基于这些观察，我们得出一些一般的固态嵌入式集群的设计标准。
In this work, we present general and robust transferable principles for the construction of quantum-mechanically treated clusters in a solid-state embedding (SSE) approach, beyond the still prevalent trial and error approach. Thereby, we probe the quality of different cluster shapes on the accuracy of chemisorption energies of small molecules and small polaron formation energies at the rutile TiO2 (110) surface as test cases. Our analyses show that at least the binding energies and electronic structures in the form of the density of states tend to be quite robust already for small, nonoptimal cluster shapes. In contrast to that, the description of polaron formation can be dramatically influenced by the employed cluster geometry possibly leading to an erroneous energetic ordering or even to a wrong prediction of the polaronic states themselves. Our findings show that this is mainly caused by an inaccurate description of the Hartree potential at boundary and surrounding atoms, which are insufficiently compensated by the embedding environment. This stresses the importance of the cluster size and shape for the accuracy of general-purpose SSE models that do not have to be refitted for each new chemical question. Based on these observations, we derive some general design criteria for solid state embedded clusters.