Two-dimensional (2D) materials combine many fascinating properties that make them more interesting than their three-dimensional counterparts for a variety of applications. For example, 2D materials exhibit stronger electron-phonon and electron-hole interactions, and their energy gaps and effective carrier masses can be easily tuned. Surprisingly, published band gaps of several 2D materials obtained with the GW approach, the state-of-the-art in electronic-structure calculations, are quite scattered. The details of these calculations, such as the underlying geometry, the starting point, the inclusion of spin-orbit coupling, and the treatment of the Coulomb potential can critically determine how accurate the results are. Taking monolayer MoS₂ as a representative material, we employ the linearized augmented planewave + local orbital method to systematically investigate how all these aspects affect the quality of G₀W₀ calculations, and also provide a summary of literature data. We conclude that the best overall agreement with experiments and coupled-cluster calculations is found for G₀W₀ results with HSE06 as a starting point including spin-orbit coupling, a truncated Coulomb potential, and an analytical treatment of the singularity at q = 0.

二维 (2D) 材料结合了许多令人着迷的特性，使其在各种应用中比三维材料更有趣。例如，二维材料表现出更强的电子-声子和电子-空穴相互作用，并且它们的能隙和有效载流子质量可以轻松调节。令人惊讶的是，已发表的通过G W方法（电子结构计算中最先进的方法）获得的几种二维材料的带隙相当分散。这些计算的细节，例如基础几何结构、起点、自旋轨道耦合的包含以及库仑势的处理，可以关键地决定结果的准确性。以单层MoS _{2为代表材料，采用线性化增强平面波+局域轨道方法系统地研究了这些因素如何影响}G ₀ W ₀计算的质量，并提供了文献数据的总结。我们得出的结论是，以 HSE06 为起点的G ₀ W ₀结果与实验和耦合簇计算具有最佳的总体一致性，包括自旋轨道耦合、截断库仑势以及q  = 0处奇点的分析处理。