Abstract As a new class of one-dimensional (1D) transition-metal monochalcogenides (TMMs) nanowires (NWs), the recently synthesized MoS NWs exhibit potential applications in two-dimensional integrated circuit. However, their mechanical behaviors remain almost unexplored. In this paper, the mechanical behaviors of MoS NWs under tensile loading are studied by classical molecular dynamics simulations together with first-principles calculations. A novel phase transformation is observed in the MoS NWs when the strain applied to them is larger than a critical value, which results in tension-induced hardening in their tensile modulus. Due to the existence of phase transformation, a complicated mechanical response is observed in MoS NWs during the entire loading process, which successively experiences the linear, plateau, stress hardening and fracture stages. The influence of various factors including the strain rate and temperature on the mechanical properties of MoS NWs such as phase transformation, Young’s modulus, fracture strength and fracture strain are also examined. The mechanical properties of MoS NWs obtained in this paper will be beneficial to their future applications in the semiconducting field. It is also expected that the results of the tension-induced phase transformation and its influence on the material properties observed in the present MoS NWs can be further extended to other 1D TMMs such as MoTe and SnSe NWs, since these 1D TMMs are found to possess the similar structure.

中文翻译：

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MoS 纳米线在张力作用下的分子动力学模拟力学行为

摘要 作为一类新的一维 (1D) 过渡金属单硫属元素化物 (TMMs) 纳米线 (NWs)，最近合成的 MoS NWs 在二维集成电路中具有潜在的应用价值。然而，它们的机械行为几乎仍未被探索。在本文中，通过经典分子动力学模拟和第一性原理计算研究了 MoS NWs 在拉伸载荷下的力学行为。当施加在 MoS NWs 上的应变大于临界值时，在 MoS NWs 中观察到一种新的相变，这导致它们的拉伸模量发生张力诱导硬化。由于相变的存在，在整个加载过程中，在 MoS NWs 中观察到复杂的机械响应，依次经历线性、高原、应力硬化和断裂阶段。还研究了包括应变速率和温度在内的各种因素对 MoS NWs 机械性能的影响，如相变、杨氏模量、断裂强度和断裂应变。本文获得的 MoS NWs 的机械性能将有利于它们在半导体领域的未来应用。还预计张力诱导相变的结果及其对当前 MoS NW 中观察到的材料性能的影响可以进一步扩展到其他一维 TMM，如 MoTe 和 SnSe NW，因为这些一维 TMM 被发现具有相似的结构。断裂强度和断裂应变也进行了检查。本文获得的 MoS NWs 的机械性能将有利于它们在半导体领域的未来应用。还预计张力诱导相变的结果及其对当前 MoS NW 中观察到的材料性能的影响可以进一步扩展到其他一维 TMM，如 MoTe 和 SnSe NW，因为这些一维 TMM 被发现具有相似的结构。断裂强度和断裂应变也进行了检查。本文获得的 MoS NWs 的机械性能将有利于它们在半导体领域的未来应用。还预计张力诱导相变的结果及其对当前 MoS NW 中观察到的材料性能的影响可以进一步扩展到其他一维 TMM，如 MoTe 和 SnSe NW，因为这些一维 TMM 被发现具有相似的结构。