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arXiv · 2509.19121

First principles and scanning tunneling spectroscopical evidences for thermodynamically stable "on-top" sulfur divacancy in monolayer WS$_{2}$

Weiru Chen·John C. Thomas·Yihuang Xiong·Zhuohang Yu·Da Zhou·Shalini Kumari·Zhongwei Dai·Joshua A. Robinson·Mauricio Terrones·Archana Raja·Sinéad Griffin·Alexander Weber-Bargioni·Geoffroy Hautier
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Abstract

Chalcogen vacancies in monolayer transition metal dichalcogenides (TMDs), such as WS$_{2}$, play a crucial role in various applications ranging from optoelectronics and catalysis to quantum information science (QIS), making their identification and control essential. This study focuses on WS$_{2}$ single vacancy and vacancy pairs. Using first principles computations, we investigate their thermodynamic stabilities and electronic structures. We identify an "on-top" divacancy configuration where two vacancies sit on top of each other to be the only energetically stable complex with a binding energy of 160 meV. We compute a small difference in electronic structure with a shift of the unoccupied state by 140 meV for the divacancy complex and observe electronic state shift during Scanning Tunneling Spectroscopy of a series of vacancy in WS$_2$ providing spectroscopical evidence for the presence of this defect.

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Weiru Chen, John C. Thomas, Yihuang Xiong, Zhuohang Yu, Da Zhou, Shalini Kumari, Zhongwei Dai, Joshua A. Robinson, Mauricio Terrones, Archana Raja, Sinéad Griffin, Alexander Weber-Bargioni, Geoffroy Hautier. 2025-09-23. First principles and scanning tunneling spectroscopical evidences for thermodynamically stable "on-top" sulfur divacancy in monolayer WS$_{2}$. https://arxiv.org/abs/2509.19121

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