Department of Physics, Izmir Institute of Technology, 35430, Izmir, Turkey.
Nanotechnology. 2017 Dec 8;28(49):495709. doi: 10.1088/1361-6528/aa94ab.
First-principles calculations based on density-functional theory are used to investigate the effects of hydrogenation on the structural, vibrational, thermal and electronic properties of the charge density wave (CDW) phase of single-layer TiSe. It is found that hydrogenation of single-layer TiSe is possible through adsorption of a H atom on each Se site. Our total energy and phonon calculations reveal that a structural phase transition occurs from the CDW phase to the T phase upon full hydrogenation. Fully hydrogenated TiSe presents a direct gap semiconducting behavior with a band gap of 119 meV. Full hydrogenation also leads to a significant decrease in the heat capacity of single-layer TiSe.
基于密度泛函理论的第一性原理计算被用来研究氢化对单层 TiSe 的电荷密度波 (CDW) 相的结构、振动、热和电子性质的影响。研究发现，通过在每个 Se 位置吸附一个 H 原子，单层 TiSe 的氢化是可能的。我们的总能量和声子计算表明，完全氢化时会发生从 CDW 相到 T 相的结构相变。完全氢化的 TiSe 呈现出直接带隙半导体行为，带隙为 119 meV。完全氢化还导致单层 TiSe 的热容显著降低。
