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Updated: Jun 12, 2025

From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding

From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding

Published on: March 24, 2018

异常格子收缩和新出现的拓相在二替代的Sm₂Ir₂O₇中

Prachi Telang¹, Abhisek Bandyopadhyay², Carlo Meneghini³

¹Department of Physics, Indian Institute of Science Education and Research Pune, Dr. Homi Bhabha Road, Pashan, Pune 411008, Pune, MH, 411008, INDIA.

Journal of physics. Condensed matter : an Institute of Physics journal

|September 24, 2024

概括

在Sm$_2$Ir$_2$O$_7$中替换 (Bi) 为 (Sm) 会导致异常格子收缩,并将材料转移到拓相. 这种过渡表明在韦尔半金属到二次金属带接触边界的量子临界点.

科学领域:

凝聚物质物理学凝聚物质物理学
材料科学材料科学材料科学
固态化学固态化学

背景情况:

像Sm$_2$Ir$_2$O$_7$这样的火氧化物以异国情调的电子特性而闻名.
调节材料的组成可以改变电子相和晶格结构.

研究的目的:

为了研究在Sm$_2$Ir$_2$O$_7$中替换Bi为Sm对其晶体结构和电子特性的影响.
探索拓相的出现,特别是韦尔和二次带接触 (QBT),作为生物度的函数.

主要方法:

用于结构分析的同步粉X射线衍射 (XRD).
对于电子和局部结构的X射线近边缘精细结构 (XANES) 和扩展的X射线吸收精细结构 (EXAFS).
电阻,磁感应和热容量测量以探测电子行为.

主要成果:

观察到一个异常的晶格收缩,高达10%的Bi替代,随后是遵守维加德定律的扩张.
电阻测量显示了从1/T行为 (韦尔阶段) 过渡到-lnT依赖 (QBT阶段) 随着Bi含量增加.
中间组合表现出 $\rm 1/T^{1/4}$ 的缩放,表明接近量子临界点.

结论:

在Sm$_2$Ir$_2$O$_7$中石的替代导致结构异常和从韦尔半金属到QBT拓相的相变.
观察到的现象与这些拓相的边界处的潜在量子临界点有关.
这项研究突出了通过组合工程在火 iridates的拓电子状态的可调性.

关键词:

异常的格子收缩收缩.铁酸铁酸盐是什么铁酸铁酸盐正方形带触摸的触摸方式量子临界点是一个量子临界点.拓阶段拓阶段是指拓阶段.韦尔半金属是一种半金属.

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