通过延长的抗结合状态引起的强晶体隔热
Ruihuan Cheng1, Chen Wang1,2, Niuchang Ouyang3
1Department of Mechanical Engineering, The University of Hong Kong, Hong Kong SAR, China.
Nature communications
|August 26, 2025
概括
研究人员合成了具有极低导热性的晶体材料AgTl2I3. 这种材料
科学领域:
- 材料科学
- 固态物理
- 热力学
背景情况:
- 晶体固体中的极端隔热通常会在室温以上表现出不寻常的导热性行为.
- 了解网格动态对于设计先进的隔热器至关重要.
研究的目的:
- 合成和表征AgTl2I3,一个新的晶体材料.
- 研究AgTl2I3的热传输特性和潜在机制.
- 探索设计具有非常低导热性的材料的策略.
主要方法:
- 结晶AgTl2I3的合成
- 从300K到523K进行热导率的实验测量.
- 综合理论计算分析格子动力学和声子传输.
- 分析晶体结构,化学结合和原子振动.
主要成果:
- AgTl2I3 具有非常低的导热率 (0.21 Wm-1K-1 在 300 K,降至 0.17 Wm-1K-1 在 523 K).
- 在Ag-I多面体中扩展的抗结合状态会削弱化学结合.
- 强烈的格子不和,由Ag原子的声驱动,导致格子软化和低声速.
- 阻碍声子传播和声子道化减少有助于低导热.
结论:
- AgTl2I3 作为理解晶体固体低导热的模型系统.
- 晶体结构和化学结合工程是设计先进的热绝缘体的可行策略.
- 这些发现为开发用于热管理应用的新材料提供了途径.
相关概念视频
Molecular and Ionic Solids
17.5K
Crystalline solids are divided into four types: molecular, ionic, metallic, and covalent network based on the type of constituent units and their interparticle interactions.
Molecular Solids
Molecular crystalline solids, such as ice, sucrose (table sugar), and iodine, are solids that are composed of neutral molecules as their constituent units. These molecules are held together by weak intermolecular forces such as London dispersion forces, dipole-dipole interactions, or hydrogen bonds, which...
Molecular Solids
Molecular crystalline solids, such as ice, sucrose (table sugar), and iodine, are solids that are composed of neutral molecules as their constituent units. These molecules are held together by weak intermolecular forces such as London dispersion forces, dipole-dipole interactions, or hydrogen bonds, which...
17.5K
Crystal Field Theory - Octahedral Complexes
27.6K
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
27.6K
Crystal Field Theory - Tetrahedral and Square Planar Complexes
44.4K
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,...
44.4K
Hybridization of Atomic Orbitals I
48.9K
The mathematical expression known as the wave function, ψ, contains information about each orbital and the wavelike properties of electrons in an isolated atom. When atoms are bound together in a molecule, the wave functions combine to produce new mathematical descriptions that have different shapes. This process of combining the wave functions for atomic orbitals is called hybridization and is mathematically accomplished by the linear combination of atomic orbitals. The new orbitals that...
48.9K
Polymer Classification: Crystallinity
3.1K
Unlike ionic or small covalent molecules, polymers do not form crystalline solids due to the diffusion limitations of their long-chain structures. However, polymers contain microscopic crystalline domains separated by amorphous domains.
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
3.1K
Metallic Solids
18.7K
Metallic solids such as crystals of copper, aluminum, and iron are formed by metal atoms. The structure of metallic crystals is often described as a uniform distribution of atomic nuclei within a “sea” of delocalized electrons. The atoms within such a metallic solid are held together by a unique force known as metallic bonding that gives rise to many useful and varied bulk properties.
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability....
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability....
18.7K


