在分层化物基矿中进行动力控制的结构转变:调节旋转裂变的方法
Yi Xie1,2, Ruyi Song3, Akash Singh1,2
1Thomas Lord Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, United States.
Journal of the American Chemical Society
|August 11, 2022
概括
研究人员通过操纵温度诱导的结构转变来证明在混合有机-无机矿中旋转分裂的动力控制. 通过控制冷却速率调节电子属性,为螺旋电子应用提供了新的途径.
科学领域:
- 材料科学
- 凝聚物质物理学
- 固态化学
背景情况:
- 由于自旋裂变,二维混合有机-无机矿 (HOIP) 对自旋电子学具有前景.
- 在HOIP中实现显著的旋转分裂和控制反向对称性破坏仍然具有挑战性.
- 目前控制HOIP中的对称性破坏的方法有限.
研究的目的:
- 通过温度诱导的结构转换来研究HOIP中的结构和电子特性.
- 探索冷却速率在控制逆对称破坏和性转移中的作用.
- 展示用于旋转应用的HOIP中旋转分割的调方法.
主要方法:
- 使用 (S-2-MeBA) 2PbI4作为研究温度诱导结构转变的模型系统.
- 使用超快速热量测量来确定结构放松时间.
- 应用密度函数理论 (DFT) 计算来分析电子带结构和旋转分裂.
主要成果:
- 在 (S-2-MeBA) 2PbI4 中观察到温度诱导的结构转变,改变了反向对称性.
- 冷却速度决定了结构转变的发生:缓慢的冷却诱导了它,而快速的冷却则抑制了它.
- 低温阶段比室温阶段更显著的旋转分裂,由DFT证实.
- 对相位转换的动力控制允许在不同结构扭曲的不同状态之间切换.
结论:
- 通过热循环对晶体转换的动力控制可以有效调节HOIP中的自旋分裂.
- 这种方法为开发自旋电子设备提供了一条新途径.
- 可以利用HOIP中的缓慢相变来切换和控制依赖于结构扭曲和格子对称性的物理现象.
相关概念视频
03:02Colors and Magnetism
12.3K
Color in Coordination Complexes
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human...
12.3K
02:42Valence Bond Theory
9.1K
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...
9.1K
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
44.0K
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,...
44.0K
02:58Crystal Field Theory - Octahedral Complexes
27.3K
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...
27.3K