Correlation between electronic and structural orders in 1T-TiSe2
Hiroki Ueda, Michael Porer, José R. L. Mardegan, Sergii Parchenko, Namrata Gurung, Federica Fabrizi, Mahesh Ramakrishnan, Larissa Boie, Martin Josef Neugebauer,… 展开作者
Hiroki Ueda, Michael Porer, José R. L. Mardegan, Sergii Parchenko, Namrata Gurung, Federica Fabrizi, Mahesh Ramakrishnan, Larissa Boie, Martin Josef Neugebauer, Bulat Burganov, Max Burian, Steven Lee Johnson, Kai Rossnagel, Urs Staub
The correlation between electronic and crystal structures of 1T-TiSe2 in the charge density wave (CDW) state is studied by x-ray diffraction. Three families of reflections are used to probe atomic displacements and the orbital asymmetry in Se. Two distinct onset temperatures are found, TCDW and a lower T* indicative for an onset of Se out-of-plane atomic displacements. T* coincides with a DC resistivity maximum and the onset of the proposed gyrotropic electronic structure. However, no indication for chirality is found. The relation between the atomic displacements and the transport properties is discussed in terms of Ti 3d and Se 4p states that only weakly couple to the CDW order.
Spectroscopic and first principle DFT+eDMFT study of complex structural, electronic, and vibrational properties of $M_2$Mo$_3$O$_8$ ($M$=Fe, Mn) polar magnets
采用光谱、X射线衍射、密度泛函理论（DFT）和密度泛函理论+嵌入动力学平均场（DFT+eDMFT）方法研究了六方结构$M_2$ Mo $_3$ O $_8$（$M$ =Fe，Mn）极性磁体的结构和电子性质.我们的实验数据是一致的，属于空间群P6 $_3$ mc的两个化合物的室温结构。在室温下的实验结构和电子性质在DFT+eDMFT方法中得到很好的再现，从而建立了其在顺磁相的预测能力。随着温度的降低，这两种化合物进行磁相变，我们认为，这种转变是并发的结构相变（从P6 $_3$ MC的对称性变化）的Fe化合物和同构过渡（没有从P6 $_3$ MC的对称性变化）的Mn化合物。此外，还讨论了Fe $^{2+}$离子中d-d电子跃迁的温度依赖行为。
Systematic analysis of structural and magnetic properties of spinel $CoB_2O_4$(B=Cr,Mn and Fe)compounds from their electronic structures
采用密度泛函理论（DFT）+U方法和广义梯度近似（GGA）研究了尖晶石化合物$CoB_2O_4$（B=Cr，Mn和Fe）的结构和磁性.我们专注于了解这些材料的性质的趋势作为B阳离子的变化，在晶体场和交换场的相对强度，通过分析它们的电子态密度。我们发现电子-电子关联在获得正确的结构态和电子基态中起着重要的作用。CoMn $_{2}$ O $_{4}$中的显著结构畸变和CoFe $_{2}$ O $_{4}$中的“倒置”亚晶格占据显著影响磁交换相互作用。从结构参数和电子结构的角度分析了磁交换相互作用的趋势。发现CoFe $_{2}$ O $_{4}$中的Fe态是非常局域化的，与位置的对称性无关，这使得它与其他两种化合物中B阳离子的态的特征非常不同.这些结果提供了有用的洞察的趋势，在CoB $_{2}$ O $_{4}$化合物的性质与B阳离子的变化，这将有助于理解最近的实验结果的Mn和Cr的掺杂在多铁性CoCr $_{2}$ O $_{4}$。
Effects of the structural distortion on the electronic band structure of {\boldmath $\rm Na Os O_3$} studied within density functional theory and a three-orbital model
Electronic and structural properties of Rh- and Pd-based kagome layered shandites from first principles
Niels Bohr Institute, University of Copenhagen（哥本哈根大学尼尔斯·玻尔研究所）；Department of Chemical Engineering and Materials Science, University of Minnesota（明尼苏达大学化学工程与材料科学系）
Direct Observation of Decoupled Structural and Electronic Transitions and an Ambient Pressure Monoclinic-Like Metallic Phase of VO$_2$
本文报道了用电子能谱、光电子能谱学和显微镜同时测量VO $_2$金属-绝缘体转变的结构和电子成分。我们表明，这些演变在不同的温度范围内，并分开一个不寻常的单斜类金属相。我们的研究结果提供了确凿的证据，新的单斜金属相，最近确定在高压和非平衡测量，是在环境压力下的热力学转变，我们讨论了这些意见的性质上的MIT VO $_2$的影响。
Anomalous contribution to the nematic electronic states from the structural transition in FeSe revealed by time- and angle-resolved photoemission spectroscopy
