Abstract In the two years, the TMDs materials perform a hugely great role in that they represent other resources of getting a material with bandgap energy and stable dynamically for electronics purposes. Many subjects have confirmed that TMDs mono or bi-layer could offer properties superior to those of graphene. Astonishingly, few of them have synthesized. Based on the density functional theory and beyond, we study the electronic, vibrational, and optical properties of new 2D materials, i.e., the alkaline-earth fluoro-halides monolayers such as PbFCl and PbFI. By computing the phonon spectra of PbFCl and PbFI monolayers, we have shown that they are dynamically stable. We obtained the bandgaps of these monolayers as achieved with the GW approximation are 6.38 and 6.64 eV. Also, we found that the strength of the electric field decreases the bandgap energy of our compounds and modifies the location of CBM and VBM. Further, we obtained by employing the picture marks seen in the calculated STM images and their accompanying geometries as creating slabs it is probable to build these 2D monolayers.

中文翻译：

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使用密度泛函理论及其他方法研究 PbFCl 和 PbFI 单层的电子和光学特性

摘要 在这两年中，TMDs 材料发挥了巨大的作用，因为它们代表了获得具有带隙能量且动态稳定的材料用于电子目的的其他资源。许多受试者已经证实，TMDs 单层或双层可以提供优于石墨烯的性能。令人惊讶的是，其中很少有人合成。基于密度泛函理论及其他理论，我们研究了新型二维材料（即碱土氟卤化物单层，如 PbFCl 和 PbFI）的电子、振动和光学特性。通过计算 PbFCl 和 PbFI 单层的声子光谱，我们已经证明它们是动态稳定的。我们获得了这些单层的带隙，GW 近似值分别为 6.38 和 6.64 eV。还，我们发现电场强度降低了我们化合物的带隙能量并改变了 CBM 和 VBM 的位置。此外，我们通过使用在计算出的 STM 图像中看到的图片标记及其伴随的几何形状来创建平板，很可能会构建这些 2D 单层。