概括
锡在高压 (39kB) 和高温 (314°C) 时表现出四角对称性. 研究人员使用X射线衍射绘制了I和II相极限的地图,高达70kb.
科学领域:
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
- 晶体学 晶体学是指结晶学.
背景情况:
- 锡在不同的压力和温度条件下经历相变.
- 了解锡相的晶体结构对于材料科学应用至关重要.
研究的目的:
- 在高压和高温下确定锡的晶体结构.
- 为了研究的化曲线和相位边界.
- 描述I和II阶段过渡的特征.
主要方法:
- 使用X射线衍射技术分析了锡的结构.
- 进行高压实验,最高达70千巴 (kb).
- 在结构分析期间,温度控制在314摄氏度.
主要成果:
- 观察到锡在39kB和314°C时具有四角对称性.
- 确定了单元细胞尺寸:a = 3.81 Å,c = 3.48 Å,其中c/a = 0.91.
- 化曲线被观察到高达45kb,I-II阶段边界被绘制为70kb.
结论:
- 该研究在特定的高压条件下提供了精确的结晶学数据.
- 的相位图得到了扩展,澄清了I和II相之间的界限.
- 这些发现有助于了解锡在极端环境中的行为.
相关概念视频
X-ray Crystallography
The size of the unit cell and the arrangement of atoms in a crystal may be determined from measurements of the diffraction of X-rays by the crystal, termed X-ray crystallography.
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
X-ray Diffraction of Biological Samples
X-ray diffraction or XRD is an analytical tool that utilizes X-rays to study ordered structures such as crystalline organic and inorganic samples, polycrystalline materials, proteins, carbohydrates, and drugs.
According to Bragg's law, when X-rays strike the sample positioned on a stage, the rays are scattered by the electron clouds around the sample atoms. The X-ray diffraction or scattering is caused by constructive interference of the X-ray waves that reflect off the internal crystal...
According to Bragg's law, when X-rays strike the sample positioned on a stage, the rays are scattered by the electron clouds around the sample atoms. The X-ray diffraction or scattering is caused by constructive interference of the X-ray waves that reflect off the internal crystal...
Determination of Crystal Structures
In the late 1800s, the revelation that light extended beyond visible wavelengths led to the discovery of X-rays by Wilhelm Roentgen. Recognized as high-energy electromagnetic radiation with short wavelengths, X-rays prompted exploration into their interaction with crystals. Max von Laue proposed in 1912 that the periodic arrangement of atoms, ions, or molecules in crystals would cause them to diffract X-rays, a hypothesis confirmed through experiments with copper sulfate and zinc sulfide...


