在化学替代的BaTiO_{3}中,极性顺序的逆化
Yang Zhang1, Suk Hyun Sung1, Colin B Clement2
1Harvard University, The Rowland Institute at Harvard, Cambridge, Massachusetts 02138, USA.
Physical review letters
|July 31, 2025
概括
研究人员观察到,在一个无序的铁电氧化物中,反向化,在较低的温度下,材料变得更加无序,与典型材料不同. 这种现象与化学混乱和随机场有关.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学是一种材料科学.
- 晶体学 晶体学是指结晶学.
背景情况:
- 远程秩序通常在低温的凝聚物质系统中出现.
- 一些具有竞争相互作用或灭混乱的系统表现出反向化,随着温度的下降变得更加混乱.
- 铁电氧化物在电子设备中至关重要,了解它们的顺序-混乱过渡至关重要.
研究的目的:
- 为了研究一个无序的铁电氧化物中反向化的现象.
- 在不同温度下可视化极端秩序在BaTi_{1-x}Zr_{x}O_{3}中的原子尺度行为.
- 了解灭化学乱在驱动逆化的作用.
主要方法:
- 在现场扫描传输电子显微镜 (STEM) 用于直接原子尺度可视化.
- 合成和表征BaTi_{1-x}Zr_{x}O_{3}与灭的化学乱.
- 对温度依赖的结构和极点排序的分析.
主要成果:
- 在BaTi_{1-x}Zr_{x}O_{3}中观察到极点顺序的反向化,与父BaTiO_{3}系统的偏离.
- 在低温下显示出一个重新进入的无序配置,在中间温度下出现一个有序状态.
- 将逆融与由Zr补充剂生成的随机场联系起来,影响热波动和结潜力之间的平衡.
结论:
- 化的化学乱可以诱导铁电氧化物逆化.
- 热波动和随机场之间的相互作用支配了这些材料中的秩序-混乱景观.
- 了解逆融对于设计具有定制性质的先进功能材料至关重要.
相关概念视频
03:37Molecular Shape and Polarity
62.1K
Dipole Moment of a Molecule
62.1K
02:27Predicting Molecular Geometry
36.1K
VSEPR Theory for Determination of Electron Pair Geometries
36.1K
02:42Valence Bond Theory
9.7K
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
9.7K
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
44.7K
Tetrahedral Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
44.7K
02:42Ionic Crystal Structures
14.8K
Ionic crystals consist of two or more different kinds of ions that usually have different sizes. The packing of these ions into a crystal structure is more complex than the packing of metal atoms that are the same size.
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
Most monatomic ions behave as charged spheres, and their attraction for ions of opposite charge is the same in every direction. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite...
14.8K
01:16Thermal Sigmatropic Reactions: Overview
2.2K
Sigmatropic rearrangements are a class of pericyclic reactions in which a σ bond migrates from one part of a π system to another. These are intramolecular rearrangements where the total number of σ and π bonds remain unchanged.
Sigmatropic shifts are classified based on an order term [i, j ], where i and j indicate the number of atoms across which each end of the σ bond migrates. Below are examples of a [3,3] sigmatropic shift in...
Sigmatropic shifts are classified based on an order term [i, j ], where i and j indicate the number of atoms across which each end of the σ bond migrates. Below are examples of a [3,3] sigmatropic shift in...
2.2K