ABSTRACT The mechanical, electrical, optical and thermoelectric properties of SrS graphene-like structure are discussed using the density functional theory and FP-Lapw method. To calculate the electrical properties, the generalized gradient approximation, Kohn–Sham, and Green function Waves function approximations are used in our correlation potential, and the optical calculations are performed based on the Time-dependent density functional theory (TDDFT), Bethe-Salpeter equation, and Random Phase approximation approximations. The structural calculations suggest the phonon stability of SrS, with an observed optical phonon gap in the range of 5–9 THz, indicating that the bonds are ionic. The electronic calculations show that the SrS graphene-like has a direct bandgap of 2.6 eV and also the static value of its real dielectric function has the maximum value with RPA, and minimum value with BSE approximations. In the BSE and TDDFT approximations, the optical behaviour of SrS graphene-like shows optical stability in the infrared, visible and UV edge regions. It has an excellent thermoelectric quality at room temperature, and remarkably its thermoelectric behaviour is stable even beyond 500 K, hence it is a good choice for power generators.

中文翻译：

---

通过 DFT 获得 SrS 石墨烯的热电和光学特性

摘要 使用密度泛函理论和 FP-Lapw 方法讨论了类 SrS 石墨烯结构的机械、电学、光学和热电特性。为了计算电特性，我们在相关势中使用了广义梯度近似、Kohn-Sham 和格林函数波函数近似，并且基于瞬态密度泛函理论 (TDDFT)、Bethe-Salpeter 进行了光学计算方程和随机相位近似近似。结构计算表明 SrS 具有声子稳定性，观察到的光学声子间隙在 5-9 THz 范围内，表明这些键是离子键。电子计算表明，类 SrS 石墨烯的直接带隙为 2。6 eV 及其实际介电函数的静态值在 RPA 中具有最大值，在 BSE 近似中具有最小值。在 BSE 和 TDDFT 近似值中，类 SrS 石墨烯的光学行为在红外、可见光和紫外边缘区域显示出光学稳定性。它在室温下具有优良的热电质量，并且在超过 500 K 时其热电行为也非常稳定，因此是发电机的理想选择。