Abstract The searching for new elemental allotropes with unique properties and potential applications has been a hot topic in the fields of condensed matter and materials science. Here, we identify a new phase of arsenic by ab-initio calculations in space group symmetry of T5 (I213, No.199), named K4 arsenic. The dynamic, thermal stabilities, and mechanical of K4 arsenic are confirmed by variety of theoretical calculations. Band structure analysis shows that K4 arsenic is a direct-gap semiconductor with gap value of 1.28 eV. We demonstrate that the band gap of K4 arsenic can be effectively modulated by pressure, and the gap nearly closes at 5 GPa. What's more, in the visible region, the K4 arsenic exhibits strong light absorption. This novel arsenic allotrope may have potential applications in photo catalysts, optoelectronics and so on.

中文翻译：

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砷 K4 晶体：一种新型稳定的直接带隙半导体同素异形体

摘要 寻找具有独特性质和潜在应用的新元素同素异形体一直是凝聚态和材料科学领域的热门话题。在这里，我们通过 T5 (I213, No.199) 空间群对称性的 ab-initio 计算确定了砷的新相，命名为 K4 砷。各种理论计算证实了 K4 砷的动态、热稳定性和机械稳定性。能带结构分析表明，K4砷是一种直接带隙半导体，带隙值为1.28 eV。我们证明 K4 砷的带隙可以通过压力有效调节，并且带隙在 5 GPa 时几乎关闭。更重要的是，在可见光区，K4砷表现出很强的吸光性。这种新型砷同素异形体可能在光催化剂、光电子学等方面具有潜在应用。