Nabi Muskan, Gupta Dinesh C
Condensed Matter Theory Group, School of Studies in Physics, Jiwaji University Gwalior-474 011 India
RSC Adv. 2019 May 21;9(28):15852-15867. doi: 10.1039/c9ra01797f. eCollection 2019 May 20.
The structural, electronic, optical, thermodynamic and thermoelectric properties of double perovskites BaMTaO (M = Er, Tm) have been studied. These alloys stabilize in cubic structure with paramagnetic phases and structural parameters that are in good agreement with experimental results. The elastic parameters reveal both materials as being super hard and brittle in nature. The band profile displays the direct bandgap semiconducting behavior of both compounds in the spin-up channels. The optical coefficients, optical conductivity, reflectivity and electron energy loss, are intended for a photon energy of up to 14 eV to perceive the optical response. The effects of temperature and pressure on the thermodynamic properties have also been evaluated the quasi-harmonic Debye model. Post-DFT treatment was performed to explore the thermoelectric properties; both perovskites exhibit a colossal power factor of 90 × 10 W m K s and 5 × 85 × 10 W m K s for BaTmTaO and BaErTaO, respectively, at 800 K.
已对双钙钛矿BaMTaO（M = Er，Tm）的结构、电子、光学、热力学和热电性质进行了研究。这些合金稳定在立方结构中，具有顺磁相，其结构参数与实验结果高度吻合。弹性参数表明这两种材料本质上都是超硬且脆性的。能带分布显示了两种化合物在自旋向上通道中的直接带隙半导体行为。光学系数、光导率、反射率和电子能量损失针对高达14 eV的光子能量进行测定，以了解光学响应。还采用准谐德拜模型评估了温度和压力对热力学性质的影响。进行了后密度泛函理论处理以探索热电性质；在800 K时，对于BaTmTaO和BaErTaO，这两种钙钛矿分别表现出90×10 W m K s和5×85×10 W m K s的巨大功率因数。
