论文标题
在压力下，在非植物酮\ b {eta} -mno2中的带隙演变与八面体的菌株之间的连接：第一个原理研究
Connection between Bandgap Evolution and Strains of Octahedron in non-Perovskite \b{eta}-MnO2 under pressure: A First Principle Study
论文作者
论文摘要
八面体旋转和失真引起的晶格失真量很高，并且对材料的特性产生深远的影响，例如其带隙，磁性和光学特性等。金红石型\ b {eta} -mno2是巨大的非二手型非perovskite apterno pervovskite的磁性材料。我们系统地研究了其稳定性，电子结构，磁性结构和光学特性，并具有密度功能理论（DFT）。我们发现，由于Mn-D和O-P状态的相互作用，键合角度与键角之间的竞争会导致其在PNNM相中的带隙扩大或缩小。我们还发现在SIO2，GEO2，SNO2和PBO2的PNNM阶段中发现了相同的压力所指定的带隙演变。八人体连接在PNNM相和PA-3相中的不同方式导致了有趣的压力诱导的带隙扩大。在PA-3阶段，可以通过满足Shockley-Queisser极限的压力将带隙调节为1.34 eV。此外，两个高压阶段可以淬灭到环境压力。它及其机械，光学和抗磁磁特性，可确保MNO2用作具有多功能的所有工作条件的光伏材料。这项研究扩展了MNO2的应用，并提供了一些新的压力诱导带隙扩大的机理。
Lattice distortion due to octahedral rotation and distortion are high focussed, and it produces profound effect on a material's properties, such as its bandgap, magnetism and optical properties etc. Rutile-type \b{eta}-MnO2 is a wide used non-Perovskite magnetic material with octahedrons. We systematically studied its stability, electronic structures, magnetic structures, and optical properties within 0-100 GPa with density-functional theory (DFT). We find that the competition between bondlength and bonding angle leads its bandgap enlarging or shrinking within in the Pnnm phase with increasing pressure, because of the interaction of Mn-d and O-p states. We also find same pressure indused bandgap evolutions in the Pnnm phases of SiO2, GeO2, SnO2 and PbO2. The different ways of octahedral connection in Pnnm phase and Pa-3 phase leads to an interesting pressure-induced bandgap enlarging. And in the Pa-3 phase, the band gap can be tuned to 1.34 eV by pressure to meet the Shockley-Queisser limit. Moreover the two high pressure phases can be quenched to ambient pressure. Together with its mechanical, optical and antiferromagnetic properties, it ensures MnO2's application as a photovoltaic material for all working condition with multi-purpose. This study extends MnO2's application and give some new mechanism of pressure induced bandgap enlargement.
