The performance of two modern density-functionals, HSE06 and TB-mBJ, on predicting electronic structures of metal oxides, chalcogenides and nitrides, is studied in terms of band gaps, band structure and projected density-of-states. Contrary to GGA, hybrid functionals and GGA+U, both new functionals are able to predict band gaps with an appreciable accuracy of 25% and thus allow the screening of various classes of (mixed) metal oxides at modest computational cost. The calculated electronic structures are largely unaffected by the choice of basis functions and software implementation.
Barium zirconium sulfide (BaZrS3) is an earth-abundant and environmentally friendly chalcogenide perovskite with promising properties for various energy conversion applications. Recently, sulfurization of oxide precursors has been suggested as a viable solution for effective synthesis, especially from the perspective of circumventing the difficulty of handling alkali earth metals. In this work, we explore in detail the synthesis of BaZrS3 from Ba-Zr-O oxide precursor films sulfurized at temperatures ranging from 700 °C to 1000 °C. We propose a formation mechanism of BaZrS3 based on a two-step …
GW quasiparticle band structures of stibnite, antimonselite, bismuthinite, and guanajuatite
采用G $_0$ W $_0$方法，对辉锑矿族的四种同结构半导体金属硫族化合物A $_2$ B $_3$（A = Sb，Bi，B = S，Se）的准粒子能带结构进行了第一性原理计算.我们进行了广泛的收敛测试，并确定准粒子的结构参数和半核心$d$电子的修正的敏感性。我们的计算表明，所有四个硫属化物表现出直接带隙，如果我们排除一些间接跃迁略低于直接间隙。相对论自旋轨道效应的Kohn-Sham能带结构进行了评估，并包括在准粒子带隙的修正。我们计算的带隙为1.5 eV（Sb $_2$ S $_3$）、1.3 eV（Sb $_2$ Se $_3$）、1.4 eV（Bi $_2$ S $_3$）和0.9 eV（Bi $_2$ Se $_3$）。通过比较我们计算的差距与理想的肖克利-奎塞尔值，我们发现，所有四个硫属化物是有前途的纳米结构的光致发光的光敏剂。
我们研究了模型硫属化物、氧化物和卤化物材料中Ruddlesden-Popper（RP）系列（An+1BnX 3 n +1）的带隙变化，以了解影响带隙演变的因素。与氧化物和卤化物相比，我们发现硫属化物的带隙随这些天然超晶格中钙钛矿块的厚度而不同地演变。我们发现，八面体旋转（即偏离B-X-B键角从180）和量子限制效应竞争决定RP相的带隙演化。这里获得的见解将使我们能够合理地设计用于电子和光电子的层状钙钛矿相。
Electronic Structure, mass fluctuation, and Localized Bond Properties of two-dimensional double-layer transition metal chalcogenide MX$_2$ (M = Mo, W; X = S, Se, Te) Calculated Based on Density Functional Theory and BBC model
Density functional theory within the local or semilocal density approximations (DFT-LDA/GGA) has become a workhorse in electronic structure theory of solids, being extremely fast and reliable for energetics and structural properties, yet remaining highly inaccurate for predicting band gaps of semiconductors and insulators. Accurate prediction of band gaps using firstprinciples methods is time consuming, requiring hybrid functionals, quasi-particle GW, or quantum Monte Carlo methods. Efficiently correcting DFT-LDA/GGA band gaps and unveiling the main chemical and structural factors involved in …
Valley- and Spin-Dependent Electronic and Transport Properties of Two-Dimensional Altermagnetic Titanium-Based Chalcogenide Halides
Northwest University（西北大学）；Shaanxi Key Laboratory for Theoretical Physics Frontiers（陕西省理论物理前沿重点实验室）；Peng Huanwu Center for Fundamental Theory（彭桓武基础理论研究中心）；Fundamental Discipline Research Center for Quantum Science and Technology of Shaanxi Province（陕西省量子科学与技术基础学科研究中心）
Electronic structure and phase stability of oxide semiconductors: Performance of dielectric-dependent hybrid functional DFT, benchmarked against $GW$ band structure calculations and experiments
The f-electron challenge: localized and itinerant states in lanthanide oxides united by GW@LDA+U
多体微扰理论的GW方法适用于镧系氧化物，使用局域密度近似加上哈伯德U校正（LDA+U）作为出发点。CeO 2和Ce 2 O3的G 0 W 0态密度和实验光谱之间的良好协议。与LDA+U方法不同，G 0 W 0在U值的物理意义范围内仅表现出对U的弱依赖性。对于整个镧系元素倍半氧化物（Ln 2 O3）系列G0W0@LDA+U再现的光学实验带隙的主要功能。由G 0 W 0预测的占据和未占据f-态的相对位置证实了从唯象理论推导出的实验猜想。
Surface Restructuring of Nickel Sulfide Generates Optimally-Coordinated Active Sites for ORR Catalysis
已经发现第一行过渡金属氧化物和硫属化物对于水和O $_2$的相互转化的性能与基于贵金属的催化剂的性能相当。第一行过渡金属离子的高不稳定性导致催化条件下的表面动力学，并导致活性位点结构不同于本体晶格的表面终止所预期的那些。虽然这些表面转化已经在许多金属氧化物上得到了很好的表征，但在电催化条件下较重的硫属化物的表面动力学在很大程度上是未知的。我们最近报道了方沸石Ni $_3$ S $_2$体相支持在良性水性条件下的有效ORR催化，并对电解质阴离子如使Pt中毒的磷酸盐表现出优异的耐受性。在这里，我们结合电化学，表面光谱和高分辨率显微镜表征的表面动力学镍$_3$ S $_2$ ORR催化条件下。我们发现，镍$_3$ S $_2$进行自限性氧化表面重组，形成约2 nm的非晶表面膜保形涂层的镍$_3$ S $_2$微晶。表面膜具有标称NiS化学计量比，并且对于ORR催化具有高活性。使用DFT计算，我们表明，在一级近似下，硫化镍的催化活性是由Ni-S配位数在表面暴露的网站通过一个简单的几何描述符。特别是，我们发现，在表面重组过程中动态形成的非晶NiS表面上的表面位点提供了一个最佳的充满活力的景观ORR催化。这项工作提供了一个系统的框架，表征丰富的表面化学的金属硫族化合物，并提供了原则，为发展更广泛的理解介导的无定形材料的电催化。
Calibrating transition metal energy levels and oxygen bands in first principles calculations: accurate prediction of redox potentials and charge transfer in lithium transition metal oxides
Stable oxide topological insulators (TIs) that could bring together the traditional oxide functionalities with the dissipationless surface states of TIs have been sought for years but none was found. Yet, heavier chalcogenides (selenides, tellurides) were readily found to be TIs. We clarify here the basic contradiction between TI-ness and stability which is maximal for oxides, and trace the basic design principles necessary to identify the window of opportunity of stable TIs. We first identify the electronic motif that can achieve topological band inversion ("topological gene") in ABO3 as bein…
Alloying behavior of wide band gap alkaline-earth chalcogenides
合金化是调整材料的一种强大工具，有助于针对各种应用设计所需的性能。在这项工作中，我们提供了一个全面的调查合成的可及性和电子性质的碱土硫属阴离子合金（CaS $_{1-x}$ O $_x$、CaS $_{1-x}$ Se $_x$、CaS $_{1-x}$ Te $_x$、SrS $_{1-x}$ O $_x$、SrS $_{1-x}$ Se $_x$、SrS $_{1-x}$ Te $_x$、MgS $_{1- x}$ O $_x$、MgS $_{1-x}$ Se $_x$和MgS $_{1-x}$ Te $_x$）。我们发现，在岩盐结构内的同构合金化是有利于所有系统，除了MgS $_{1-x}$ Te $_x$，这是预测的岩盐和纤锌矿结构之间的异质合金。S和Se的合金被证明是容易获得的所有阳离子与低的可溶解性临界温度，使连续调谐的电子性能在整个组合物空间。S和Te的合金具有更高的临界温度，但可以通过非平衡合成策略获得，并且在此预测具有用于光电子学的期望的电子性质，其具有比S和Se的合金更宽的带隙和更低的有效质量。MgS $_{1-x}$ Te $_x$中的阴离子合金化使纤锌矿结构在组成空间的显著部分上稳定，这可以使其作为透明导电材料特别感兴趣，因为其比岩盐结构更低的有效质量和更高的带隙。零点校正的无规相近似（RPA）的能量进行计算，以解决小的多晶型物的Mg化合物的能量差，并被证明…
