In this paper, based on the first principles, we study the properties of silicon carbide nanowires (SiCNWs) passivated by monovalent hydrogen (H), heptavalent fluorine (F) and chlorine (Cl) atoms at the electronic level to reveal the mechanism of interaction between different valence electrons in the passivation process. The results show that the passivation can improve the inhomogeneity of the surface and internal Si–C bonds, and improve the stability of the SiCNWs structure. The structure of F-SiCNWs is the most stable. Meanwhile, passivation increases the bandgap of the SiCNWs, and the bandgap of H, F and Cl passivation SiCNWs decreases successively, this is because the potential energy of H-1s, F-2p and Cl-3p interacting with Si-3p decreases in turn. Besides, heptavalent F and Cl passivation can regulate some optical properties of the SiCNWs to the deep-ultraviolet light regions such as absorption, conductivity, refractive index and loss function. Monovalent H passivation can regulate some optical properties of the SiCNWs to the vacuum ultraviolet light region (UVD). These studies have potential application value for the development of deep-ultraviolet micro–nano devices.

中文翻译：

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不同价原子对碳化硅纳米线表面钝化的影响

在本文中，基于第一原理，我们在电子水平上研究了单价氢（H）、七价氟（F）和氯（Cl）原子钝化的碳化硅纳米线（SiCNWs）的性质，以揭示相互作用的机制。钝化过程中不同价电子之间的关系。结果表明，钝化可以改善表面和内部Si-C键的不均匀性，提高SiCNWs结构的稳定性。F-SiCNWs 的结构是最稳定的。同时，钝化增加了SiCNWs的带隙，H、F和Cl钝化SiCNWs的带隙依次减小，这是因为H-1s、F-2p和Cl-3p与Si-3p相互作用的势能依次减小. 除了，七价F和Cl钝化可以调节SiCNWs对深紫外光区域的一些光学特性，如吸收、电导率、折射率和损耗函数。单价H钝化可以将SiCNW的一些光学性质调节到真空紫外光区（UVD）。这些研究对于深紫外微纳器件的开发具有潜在的应用价值。