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arXiv · 2004.11481

Predicting A Novel Phase of 2D SiTe$_2$

Romakanta Bhattarai·Xiao Shen
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Abstract

Layered IV-VI$_2$ compounds often exist in the CdI$_2$ structure. Using the evolution algorithm and first-principles calculations, we predict a novel layered structure of silicon ditelluride (SiTe$_2$) that is more stable than the CdI$_2$ phase. The structure has a triclinic unit cell in its bulk form and exhibits the competition between the Si atoms' tendency to form tetrahedral bonds and the Te atoms' tendency to form hexagonal close-packing. The electronic and vibrational properties of the predicted phase are investigated. The effective mass of electron is small among 2D semiconductors, which is beneficial for applications such as field-effect transistors. The vibrational Raman and IR spectra are calculated to facilitate future experimental investigations

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Romakanta Bhattarai, Xiao Shen. 2020-04-23. Predicting A Novel Phase of 2D SiTe$_2$. https://arxiv.org/abs/2004.11481

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