Computational 2D Materials Database: Electronic Structure of Transition-Metal Dichalcogenides and Oxides
Computational 2D Materials Database: Electronic Structure of Transition-Metal Dichalcogenides and Oxides
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DOI：
10.1021/acs.jpcc.5b02950
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发表时间：
2015-06-11
影响因子：
3.7
通讯作者：
Thygesen, Kristian S.
中科院分区：
文献类型：
--
作者：
Rasmussen, Filip A.;Thygesen, Kristian S.
我们提出了一个全面的第一性原理研究的电子结构的51个半导体单层过渡金属dichalcogenides和氧化物在2H和1T六方相。在G（0）W（0）近似下计算了自旋轨道耦合的准粒子（QP）能带结构，并与不同的密度泛函理论描述进行了比较。与GW计算收敛的二维（2D）材料的陷阱一起讨论可能的解决方案。单层能带边缘相对于真空的位置被用来估计在各种异质结界面处的能带对准。的能带结构的面内晶格常数的敏感性进行了分析和合理化的电子结构。最后，q依赖的介电函数和有效的电子和空穴的质量从QP能带结构，并作为输入到一个二维类氢模型估计激子结合能。在整个论文中，我们专注于电子结构的趋势和相关性，而不是对特定材料的详细分析。所有的计算数据都可以在一个开放的数据库中获得。
We present a comprehensive first-principles study of the electronic structure of 51 semiconducting monolayer transition-metal dichalcogenides and -oxides in the 2H and 1T hexagonal phases. The quasiparticle (QP) band structures with spin-orbit coupling are calculated in the G(0)W(0) approximation, and comparison is made with different density functional theory descriptions. Pitfalls related to the convergence of GW calculations for two-dimensional (2D) materials are discussed together with possible solutions. The monolayer band edge positions relative to vacuum are used to estimate the band alignment at various heterostructure interfaces. The sensitivity of the band structures to the in-plane lattice constant is analyzed and rationalized in terms of the electronic structure. Finally, the q-dependent dielectric functions and effective electron and hole masses are obtained from the QP band structure and used as input to a 2D hydrogenic model to estimate exciton binding energies. Throughout the paper we focus on trends and correlations in the electronic structure rather than detailed analysis of specific materials. All the computed data is available in an open database.