相关实验视频

Updated: Jul 12, 2025

$Synthesis and Microdiffraction at Extreme Pressures and Temperatures$

Synthesis and Microdiffraction at Extreme Pressures and Temperatures

Published on: October 7, 2013

由X射线驱动的钻石的非热结构转换

Philip Heimann¹, Nicholas J Hartley², Ichiro Inoue³

¹Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA.

Structural dynamics (Melville, N.Y.)

|October 30, 2023

概括

强烈的X射线脉冲会诱导钻石的非热结构变化,导致晶格破坏,最终在高剂量下形成石墨. 这些发现与先进的计算模拟相一致.

科学领域:

材料科学材料科学材料科学
凝聚物质物理学凝聚物质物理学
射线科学X射线科学X射线科学

背景情况:

强烈的X射线自由电子激光 (XFEL) 脉冲可以驱动材料中的非热相转换.
钻石独特的晶体结构易于在极端条件下发生变化.

研究的目的:

为了研究钻石中X射线诱导的结构转变的动态.
为了确定钻石中石墨化的剂量值.

主要方法:

在SACLA利用探头XFEL实验来研究钻石.
分析了衍射模式,以追踪随时间 (0-250 fs) 和不同X射线剂量 (0.9-8.0 eV/原子) 的结构变化.
进行了Debye-Waller分析,并将实验数据与XTANT+模拟进行了比较.

主要成果:

随着时间的推移,观察到钻石衍射峰值强度 (111,220,311) 的下降,这表明了晶格障碍.
德拜-沃勒分析揭示了异构的原子位移,更大的垂直到111平面.
在超过1.2 eV/原子剂量值的33毫秒延迟后确认了石墨化 (002石墨峰).

结论:

在钻石中,X射线脉冲会诱导显著的非热结构转变和破坏.
钻石的石墨化发生在特定的X射线剂量值以上.
实验发现与X射线物质相互作用的混合计算模型一致.

更多相关视频

An Externally-Heated Diamond Anvil Cell for Synthesis and Single-Crystal Elasticity Determination of Ice-VII at High Pressure-Temperature Conditions

An Externally-Heated Diamond Anvil Cell for Synthesis and Single-Crystal Elasticity Determination of Ice-VII at High Pressure-Temperature Conditions

Published on: June 18, 2020

$Characterization of Ultra-fine Grained and Nanocrystalline Materials Using Transmission Kikuchi Diffraction$ 09:13

Characterization of Ultra-fine Grained and Nanocrystalline Materials Using Transmission Kikuchi Diffraction

Published on: April 1, 2017

相关概念视频

$X-ray Diffraction of Biological Samples$ 01:10

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...

X-ray Crystallography

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...