Name: crystal structure using x-ray diffraction
Uploaded: 2023-04-30T07:02:53.000Z
Duration: 9 min 31 s
Channel: JoVE

K12 Standards

ohios-learning-standards-and-model-curriculum

Ohio’s Learning Standards and Model Curriculum

9-12

Physical Geology

Minerals

Crystallinity (crystal structure)

X-ray Diffraction

以下程序适用于特定的 XRD 仪器及其相关软件，在使用其他仪器时可能会有一些变化。
<ol><li>我们将在 P 分析 Alpha-1 XRD 仪器上检查 Ni 粉末样本。</li>
	<li>首先，选择蒙版，根据样品直径固定光束尺寸。光束的占地面积不得以最小 μ 值（通常为 + 70-100） 大于样品。对于宽度 α 的样本，光束大小应为 [lt; ]。</li>
	<li>在样品微调器阶段加载样品，并将样品锁定到位。样本微调器有助于在空间上随机化样本与 X 射线源的曝光。</li>
	<li>选择 XRD 扫描的角度范围。例如，15-90 度是一个典型的范围。</li>
	<li>选择步长大小，即2°中的增量和集成（计数）时间。对于广角扫描，通常默认为 0.05 度步长大小和 4 秒集成。</li>
	<li>通过此初始扫描确定所有峰值位置后，如果需要来自这些峰值的高分辨率数据，后续扫描可以使用较小的角度步长大小关注特定峰值周围的较窄扫描范围。</li>
</ol>

这是标准 XRD 实验的演示。本实验中检验的材料为粉末状，但只要样品具有可与样品级平面平行的平面，XRD与固体材料同样有效。
XRD 是一种相当普遍的方法，用于确定材料中晶体顺序的存在（或不存在）。除了确定晶体结构的标准应用外，XRD 还经常用于获取各种其他结构信息，例如:
<ol><li>材料的结构是否无定形（以衍射强度宽的驼峰和缺乏可辨的晶体峰为特征），</li>
	<li>样品是否是由多个晶体相组成的复合材料，如果是，确定每个阶段的分数，</li>
	<li>确定材料是否为非晶形/结晶复合材料</li>
	<li>确定材料的颗粒/颗粒大小，</li>
	<li>确定材料中的纹理程度（颗粒的首选方向）。</li>
</ol>

衍射峰位置与晶体结构的关系:
当波长足够小的光波在晶格上发生时，它们会从晶格点衍射。在某些入射角度，衍射平行波建设性地干扰并产生可探测的强度峰值。W.H. Bragg 确定了图 1 所示的关系，并推导出了相应的方程:
n = = 2dhkl辛 [ 1]
此处 * 是使用的 X 射线的波长，dhkl是具有（hkl） Miller 指数* 的特定平面集之间的间距*，而α是测量衍射峰的发生率角。最后，n 是表示衍射的"谐波顺序"的整数。例如，在n=1，我们有第一次谐波，这意味着X射线通过晶体（相当于2dhkl sin）的路径正好是1μ，而在n=2，衍射路径是2°。我们通常可以假设 n=1，通常 n=1 表示[lt; sin-1（2+/dh'k'l'）]，其中 h'k'l'是显示衍射实验中第一个峰值（在最低 2° 值）的平面的 Miller 索引。Miller 指数是一组三个整数，构成用于识别晶体中方向和平面的符号系统。对于方向，[h k l] Miller 指数表示沿方向的两个点的分别 x、y 和 z 坐标（在笛卡尔坐标系中）的正一点差。对于平面，平面的 Miller 指数（h k l）只是垂直于平面方向的 h k l 值。
在反射模式下的典型 XRD 实验中，X 射线源固定在位，样品相对于 X 射线光束旋转超过 α。探测器拾起衍射光束，必须以两倍速率旋转，以±的速度保持样品旋转（即，对于给定的样品角度 α，探测器角度为 2°）。实验的几何形状如图 1 所示。
<img alt="Figure 1" src="/files/ftp_upload/10446/10446fig1v2.jpg"> 图1:布拉格定律的例证。
当观察到强度的峰值时，方程 1 必然满足。因此，我们可以根据观测这些峰值的角度计算 d 间距。通过计算多个峰的 d 间距，可以使用数据库（如 Hanawalt 搜索手册）或使用的 XRD 软件数据库库来识别晶体类和晶体结构参数材料样本。
我们将假设正在调查的样品不是一个晶体。如果样本是具有与样品表面平行的特定（h_k_l_）平面的单一晶体，则需要旋转，直到满足（h_k_l_）的布拉格条件，才能看到衍射强度（n=1）的峰值，其谐波（h_k_l_）峰值（例如 n=2）在较高角度也能检测到。在所有其他角度，单个晶体样品中没有峰值。相反，让我们假设样品是多晶或粉末，具有统计上显著数量的晶体颗粒或粉末颗粒由事件X射线束照亮。在此假设下，样本由随机定向颗粒组成，所有可能的晶格平面具有类似的统计概率。
dhkl 和单位细胞参数之间的关系如下，公式 2-7 用于 7 个晶体类、立方、四角、六边形、菱形、胸腔、单临床和三临床。单位单元参数由 7 个晶体类的单位单元边缘的长度 （a、b、c）和角度 （*、 *、 *） 组成（图 1x 显示了其中一个晶体类的示例:a_b_c 和 +=====900）的四角结构。使用多个衍射峰值位置（即几个不同的dhkl值），可以唯一求解单位单元参数的值。
<img alt="Figure 2" src="/files/ftp_upload/10446/10446fig2.jpg"> 图2:四角结构为七种晶体类之一。
立方 （a = b = c; = = = = = = = 900）:
<img alt="Equation 1" src="/files/ftp_upload/10446/10446eq1.jpg" style="opacity: 0.9; font-size: 14px;">[2]
四联体 （a = b + c; √ √ √ √ √ √ √ √ 900）:
<img alt="Equation 2" src="/files/ftp_upload/10446/10446eq2.jpg" style="opacity: 0.9; font-size: 14px;">[3]
六角形 （a = b + c; = = = = 900;= 1200）:
<img alt="Equation 3" src="/files/ftp_upload/10446/10446eq3.jpg" style="opacity: 0.9; font-size: 14px;">[4]
奥索霍比奇 （a + b + c; √ √ √ √ √ √ √ √ 900）:
<img alt="Equation 4" src="/files/ftp_upload/10446/10446eq4.jpg" style="opacity: 0.9; font-size: 14px;">[5]
隆博面体 （a = b + c; √ √ √ √ √ √ √ √ √ ） 900）:
<img alt="Equation 5" src="/files/ftp_upload/10446/10446eq5.jpg" style="opacity: 0.9; font-size: 14px;">[6]
单体诊所 （a = b + c; √ √ √ √ √√ √ √ √ √ √ √ √ ）
<img alt="Equation 6" src="/files/ftp_upload/10446/10446eq6.jpg" style="opacity: 0.9; font-size: 14px;">[7]
三联诊所 （a + b + c; # # + + + + = = 900）:
      <img alt="Equation 7" src="/files/ftp_upload/10446/10446eq8v2.jpg">[8]
衍射峰强度与晶体结构的关系:
接下来，我们研究XRD模式中导致强度的因素。这些因素可以分解为 1） 直接来自材料的独特结构方面（结构中散射原子的特定类型和位置）和 2） 对材料不特定于材料的贡献。在前者中，有两个因素:"吸收因子"和"结构因素"。吸收因素主要取决于材料在进出时吸收X射线的能力。只要样品不薄（样品应比 X 射线的衰减长度厚 3 倍），此因子就不存在依赖性。换句话说，吸收因子对不同峰的强度的贡献是恒定的。"结构因子"直接影响特定峰的强度，这是结构的直接结果。其余因子"多重性"，它占属于同一族的所有平面，因为它们是对称相关的，而来自 XRD 实验几何体的"洛伦兹-极化"因子也影响峰的相对强度，但它们不是材料所特有的，并且可以很容易地用分析表达式来解释（即XRD分析软件可以去除它们与分析功能）。
<img alt="Figure 3" src="/files/ftp_upload/10446/10446fig3.jpg"> 图3:三衍射射线路径，其中光线11'和22'满足布拉格条件，而射线33'的结果是由原子（红色圆圈）在任意位置散射的结果。
作为材料对XRD峰的相对强度的独特结构贡献的唯一因素，结构因子非常重要，需要仔细观察。在图 2 中，我们假设第1阶布拉格衍射条件（请记住，这对应于 n_1）在光线11'和射线22'之间得到满足，它们分散在 h00 方向的两个原子平面上（使用前面描述的 Miller 指数表示法）相隔一个距离 d。在此条件下，射线11'和射线22'之间的路径长度差为 ±（22'-11'） = SA = AR = = = 。因此，衍射射线1和2之间的相移是±22'-11' =（+（22'-11'）/+） 2= = 2°（假设立方对称，因此，d = h00 方向的a/h]。
在分析几何学中，通过几个步骤可以显示，相移（[33'-11']）与射线3衍射的任意对象原子的任意平面，间隔任意距离x，由:[（33'-11'） ]2°hu，其中u_x/a（a是（h00）方向的单位单元参数。以其他两个正交方向（0k0）和（00l）和v_y/a和w_z/a作为y-和z方向中的小数坐标，相移的表达式延伸到+2°（hu_kv_lw）。现在，由j-th原子分散在单元单元中的X射线波将有一个散射振幅fj和一个相位=j，这样描述它的函数就是<img alt="Equation 8" src="/files/ftp_upload/10446/10446eq8.jpg" style="opacity: 0.9; font-size: 14px;">。因此，我们寻求的结构因子是单元单元中所有唯一原子的所有散射函数的总和。此结构因子 F 给出如下:
<img alt="Equation 9" src="/files/ftp_upload/10446/10446eq9v2.jpg">[9]
结构因子贡献的强度因子为I=F2。
根据特定平面（h，k，l）原子的位置（u，v，w），存在存在建设性、破坏性或中间的散射波之间的干扰，这种干扰直接影响XRD峰的振幅代表（hkl）平面。
现在，强度图，I，与2°是XRD实验中测量的。晶体类型和相关单位单元参数（a、b、c、α、α和α）的确定可以通过观察系统存在/峰缺失、使用方程 2-9、将值与数据库进行比较、使用推导和消除过程来进行分析。如今，这个过程是相当自动化的各种软件链接到晶体结构数据库。

x 射线衍射

资料来源:佐治亚州佐治亚州理工学院材料科学与工程学院费萨尔·阿拉姆吉尔，佐治亚州亚特兰大
X射线衍射（XRD）是材料科学中用于测定材料原子和分子结构的技术。这是通过用事件 X 射线照射材料样本，然后测量材料散射的 X 射线的强度和散射角度来实现的。散射 X 射线的强度绘制为散射角的函数，材料的结构根据位置、角度和散射强度峰的强度进行分析来确定。除了能够测量晶体中原子的平均位置外，还可以确定实际结构如何偏离理想结构（例如来自内部应力或缺陷）的信息。
X射线的衍射是XRD方法的核心，是一般X射线散射现象的子集。XRD 通常用于表示可以广角 X 射线衍射 （WAXD），属于使用弹性散射 X 射线波的几种方法。其他基于弹性散射的 X 射线技术包括小角度 X 射线散射 （SAXS），其中 X 射线在样本上通常偏射在 0.1-100的小角度范围内。SAXS 测量几纳米或更大（如晶体上部结构）的尺度的结构相关性，以及测量薄膜厚度、粗糙度和密度的 X 射线反射率。WAXD覆盖的角度范围超过100。

在图 4中，我们看到 Ni 粉末样品的 XRD 峰值。请注意，观测到的峰值（例如{111}、{200}）适用于具有h、k和l的所有偶数或全部奇数组合的峰。Ni 是面向面的立方 （FCC），在所有 FCC 结构中，由于散射 X 射线的破坏性干扰，对应于 [hkl]平面的峰值，其中h、k和l是偶数和奇数整数的混合物。缺少与平面对应的峰，如{210}和{211}。这种现象称为系统存在和缺失规则，它们为评估样品的晶体结构提供了一个分析工具。
<img alt="Figure 4" class="xfigimg" src="/files/ftp_upload/10446/10446fig4.jpg"> 图4:显示了以面为中心的立方结构的NiXRD扫描。

X 射线衍射

Source: Faisal Alamgir, School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA
X-ray diffraction (XRD) is a technique ...

X 射线衍射是一种用于确定材料原子和分子结构的技术。固体具有晶体结构，这对应于周期性重复的原子的微观排列。通过对平面进行铆钉，可以形成特定对称的 3-D 结构。这些结构安排产生了特定的填料几何形状，该几何形状决定了材料的物理和化学特性。例如磁化、导热性或延展性。从材料上反射 X 射线可以揭示其结构的内部细节。本视频将说明材料上 X 射线衍射的一般原理，以及如何在实验室中使用这种现象来确定材料的结构和化学成分。首先，让我们仔细看看晶体。它由原子晶格组成，这些原子晶格分布在周期性地被几埃的距离 dhkl 隔开。H、k、l 是米勒指数，一组三个整数构成了用于识别晶体内方向和平面的符号系统。晶体中最小的重复结构称为晶胞。形成晶格的晶胞的不同角度、α、β、gamma 和长度 a、b、c 将产生不同的对称性。有七个晶体系统。立方、四方、斜方、菱面体、单斜方、三斜方和六方。可以计算每个晶体类别的晶胞参数和米勒指数之间的关系。波长 lambda 的电磁可以具有与晶体晶格内平面之间的差异相似的尺寸。这些对应于 X 射线光谱范围内的波长。当 X 射线光波以入射角 θ 照射晶体时，它们会穿过晶体传播并遇到晶格点，从中分离出来。布拉格定律将这些参数关联起来，其中 n 是表示衍射的谐波阶数的整数。对于给定的 lambda，只有特定角度 theta 会引起折射。这是晶体结构的独特特征。在实验中，样品旋转，收集散射 X 射线的探测器在达到这些特征角度时记录强度峰值。然后，可以提取满足布拉格定律的每个角度的晶格间距 DHKL。使用对应于几个不同 DHKL 值的多个衍射峰位置，可以独特地求解晶胞的参数。两个主要因素会影响峰的相对强度。首先，有非结构性的贡献，包括材料吸收 X 射线的能力，以及 XRD 实验的几何形状。这些可以在实验数据的后处理中考虑。其次，也是最重要的一点，材料的结构贡献与 XRD 的相对强度有关。每个衍射峰实际上是由晶胞中所有唯一原子衍射的多条射线路径的所有散射振幅的总和。如果散射光同相，则存在构造干涉。而如果它们异相，则存在破坏干扰。这些干扰直接影响 XRD 峰的振幅，代表晶体的 HKL 平面。现在，我们将看到这些原理如何应用于实际的 X 射线衍射实验。在开始之前，请仔细检查 XRD 仪器并评估其状态和安全性。XRD 用户必须接受基本辐射安全培训，然后才能使用该仪器。然后继续进行样品制备。在本实验中，我们使用压制颗粒形式的镍粉样品。重要的是样品不薄，并且至少应比 X 射线的衰减长度厚三倍。请注意，以下程序适用于特定的 XRD 仪器及其相关软件，使用其他仪器时可能会有一些变化。将样品加载到样品旋转台中，并将样品锁定到位，确保样品的照射面与样品台平行。使用面罩根据样品直径调整仪器的 X 射线束尺寸。在最小的入射角下，光束的占地面积必须小于样品宽度。现在是时候选择采集参数了。首先，选择 XRD 扫描的角度范围。通常，范围从 15 到 90 度。然后，选择度步长以及扫描的每个角度的积分时间。接下来，进行数据采集。扫描后，获得强度与 theta 角度的函数关系图。从此初始扫描中，选择特定峰并确定峰位置。重复采集，这次将重点放在特定峰周围的较窄扫描范围内。使用较小的角度步长可获得更高分辨率的数据。数据采集完成后，可以分析数据以识别材料的结构。使用仪器软件和数据库库，可以识别光谱的每个峰，并将其与晶体排列的特定对称性相关联。在镍粉样品的这种特殊情况下，光谱显示对应于 one one one 对称性的第一个峰。第二个峰与两个零、零对称性等相关联。然后，软件确定这种特定的对称性组合对应于面心立方结构，并确定样品是镍粉。X 射线衍射是确定材料中是否存在晶体学顺序的标准方法。它通常用于获取有关晶体中的内应力和缺陷或复合材料中的多个晶体学相的各种其他结构信息。XRD 技术还用于生物学，以确定蛋白质和核酸等生物大分子的结构和空间方向。特别是，这就是 DNA 双螺旋结构被发现的方式，从而获得了 1962 年的诺贝尔生理学或医学奖。用于采矿目的甚至行星勘探的矿物地球化学研究也利用了 XRD 技术。想想火星上的好奇号探测器，它的十台科学仪器中有一个 XRD 探测器，用于分析火星土壤的成分。您刚刚观看了 Jove 对 X 射线衍射的介绍。现在，您应该了解固体的晶体结构和 X 射线衍射的原理。您还应该了解如何在实验室中使用 XRD 技术来获得材料的结构和化学成分。感谢观看！

Education

教育

JoVE Science Education

Engineering

工程学

Materials Engineering

材料工程

crystal structure using x-ray diffraction

X-ray diffraction is a materials science method for finding crystal structure. It uses incident X-rays that strike a sample and scatter from its atoms and molecules. The scattered X-rays are measured by their intensity and scattering angle.

The results are plotted as intensity versus angle. Scientists then analyze the position of the peaks and their strength to determine the structure of the material. This method can also show how a real crystal differs from an ideal one. It can reveal effects such as internal stress and defects.

X-ray diffraction is part of a broader group of X-ray scattering methods. It is often used to mean wide-angle X-ray diffraction, or WAXD. WAXD covers scattering at angles above 10 degrees.

Other elastic scattering methods include small angle X-ray scattering, or SAXS, and X-ray reflectivity. SAXS uses a small angular range of about 0.1 to 10 degrees and measures structural correlations on the scale of several nanometers or larger, such as crystal superstructures. X-ray reflectivity is used to measure the thickness, roughness, and density of thin films.

Crystal Structure Using X-ray Diffraction

crystal-structure-using-x-ray-diffraction

optical materialography part 1: sample preparation

optical-materialography-part-1-sample-preparation

Preparing Solid Samples for Optical Microscopy

Optical microscopy of solid materials starts with careful sample preparation. Materialography is the study of microscopic structures in solids and the features seen in those images. It helps reveal details such as porosity, grain size and shape, and whether the microstructure shows anisotropy, or direction-dependent structure. This lesson focuses on the preparation steps used before optical microscopy. It covers the techniques and procedures needed to ready a solid material sample for imaging.

optical materialography part 2: image analysis

optical-materialography-part-2-image-analysis

Quantifying Microstructure in Optical Materialography

Optical materialography can be used to measure the microstructure of solid materials. It focuses on the microscopic structures seen in an exposed surface and uses them to study the material more deeply. A common goal is to estimate the three-dimensional microstructure of a sample from a two-dimensional cross section. This approach relies on the structural features visible in the image. It helps turn surface observations into quantitative data about the material. X-ray tomography can also...

x-ray photoelectron spectroscopy

XPS Surface Analysis of Materials

X-ray photoelectron spectroscopy, or XPS, is a surface analysis method for studying materials. It measures elemental composition, empirical formula, chemical state, and electronic state of the elements in a sample. Because the signal comes from the top few nanometers, XPS is especially useful for examining surfaces. To collect an XPS spectrum, a material is irradiated with an X-ray beam. At the same time, the instrument measures the kinetic energy and number of electrons that escape from the...

x-ray diffraction

X-ray diffraction is a materials science method for finding crystal structure. It uses incident X-rays that strike a sample and scatter from its atoms and molecules. The scattered X-rays are measured by their intensity and scattering angle. The results are plotted as intensity versus angle. Scientists then analyze the position of the peaks and their strength to determine the structure of the material. This method can also show how a real crystal differs from an ideal one. It can reveal effects...

focused ion beams

Focused Ion Beams in Microfabrication

Focused ion beams are used in microfabrication and nano-fabrication. A focused ion beam, or FIB, is an instrument that can fabricate, trim, analyze, and characterize materials on micro- and nano-scales. These tools are used in many fields, from nano-electronics to medicine. FIB systems work with a beam of ions. That beam can mill, or sputter, material away. It can also deposit material and image surfaces at small scales. In many research labs, the ion column of a FIB is integrated with the...

directional solidification and phase stabilization

directional-solidification-and-phase-stabilization

Zone Melting for Alloy Refining

Zone melting directional solidification is a metallurgical process used to move a narrow molten region through a crystal, usually a bar-shaped sample. A furnace travels along the rod, so the molten zone moves from one end of the bar to the other. This controlled motion changes how material forms as it solidifies. In alloys, solute atoms tend to separate into the melt. Impurities also concentrate in the molten zone instead of staying in the solid. As the molten region moves forward, it carries...

differential scanning calorimetry

Measuring Polymer Crystallinity with DSC

Differential scanning calorimetry, or DSC, is a method used to measure the thermal properties of materials. It helps scientists see how much heat a material stores as it warms up. This heat storage is called heat capacity. DSC also measures the heat absorbed or released during chemical reactions and phase changes. From these measurements, it can help determine other properties such as glass transition temperature and polymer crystallinity. Polymers often have long, chain-like structures that...

thermal diffusivity and the laser flash method

thermal-diffusivity-and-the-laser-flash-method

How Laser Pulses Measure Heat Flow

Laser flash analysis measures thermal diffusivity, which describes how fast heat moves through a material compared with how much heat it stores. This material-specific property helps show how a sample transfers thermal energy and how it responds to temperature changes. Thermal diffusivity is related to thermal conductivity, the measure of how heat moves through a material because of a temperature difference. That relationship also depends on the material’s density, shown as ρ, and its specific...

electroplating of thin films

Fast Metal Coating Without a Vacuum

Electroplating is a way to add a thin metal coating to a surface using electric current. In this process, dissolved metal cations are reduced and form a film on an electrode. The method is also called electrodeposition. This page also compares electroplating with other thin film deposition methods. Chemical vapor deposition, or CVD, uses a gas-phase precursor. Spin coating spreads a liquid precursor by spinning it outward. Dip coating is similar, but the substrate is fully submerged instead of...

analysis of thermal expansion via dilatometry

analysis-of-thermal-expansion-via-dilatometry

Using Dilatometry to Measure Heating Effects

Dilatometry measures how a material changes in size as temperature changes. It can track changes in length, area, shape, or volume. The method is used to calculate thermal expansion, which is the expansion of a substance when it is heated. Thermal expansion matters when choosing materials for systems that face changing temperatures. Some materials need high thermal expansion, such as the liquid in a thermometer, because the change helps detect temperature shifts. Other uses need materials with...

electrochemical impedance spectroscopy

Why AC Signals Matter in Impedance

Electrical impedance describes how a circuit element resists the flow of electricity. It is a more general measure than electrical resistance, especially when a circuit is not simple enough to be described by resistance alone. Resistance is the ability of a circuit element to resist current. It is defined by Ohm's law, which relates voltage and current. That relationship works well for ideal resistors, but many real circuit elements are more complex. When an alternating current, or AC, is...

ceramic-matrix composite materials and their bending properties

ceramic-matrix-composite-materials-and-their-bending-properties

Bone-Inspired Ceramic Composites in Bending

Bone helps show how ceramic-matrix composites work. In this material system, the ceramic part gives compressive strength, while the polymer fiber reinforcement adds tensile and flexural strength. By changing the amounts of ceramic and polymer, engineers can make materials for specific uses. This idea matters in biomedical engineering, where replacing or copying bone after disease or traumatic injury is an important goal. For this study, plaster of Paris, a calcium sulfate compound, is used to...

nanocrystalline alloys and nano-grain size stability

nanocrystalline-alloys-and-nano-grain-size-stability

Keeping Nanocrystalline Alloy Grains Small

Nanocrystalline alloys are metals with grain sizes smaller than 100 nm. These tiny grains can give the material enhanced physical and mechanical properties. That is why nanocrystalline alloys are used or studied for semiconductor devices, biosensors, and aerospace parts. A major challenge is making dense bulk materials from these alloys. To reach close to 100% density, the material must be processed with elevated temperature and pressure. But as temperature and pressure rise, the small grains...

hydrogel synthesis

Hydrogels and Their Water Absorption

Hydrogels are cross-linked polymers that can absorb water and swell. They are made with relatively simple procedures and inexpensive materials, which makes them useful for many school-level chemistry and materials science topics. A hydrogel starts with a polymer backbone built from monomer reagents. An initiator makes the polymer reactive, and a crosslinking species connects the chains together. This network gives the material its final structure. Water absorption is one of the key features...

materials engineering

该系列采用尖端材料分析和表征方法，并介绍了一系列用于新技术和应用的先进材料和工艺。

Learn how X-ray diffraction uses scattered X-rays to identify crystal structure, detect defects, and distinguish WAXD, SAXS, and X-ray reflectivity.

Crystal Structure Using X-ray Diffraction | JoVE K12

criteria-mineral-crystalline-solid-occurs-nature-inorganic-defined

Criteria of a mineral (crystalline solid, occurs in nature, inorganic, defined chemical composition)

Virginia  Standards of Learning

HIgh School

Earth Science

ES.4

ES.4.c

south-carolina-college-and-career-ready-science-standards

South Carolina College and Career Ready Science Standards

High School

Chemistry

Matter and Its Interactions

C-PS1-1

C-PS1-3.

motion-and-stability-forces-and-interactions

Motion and Stability: Forces and Interactions

C-PS2-6.

Faisal Alamgir

School of Materials Science and Engineering

Georgia Institute of Technology

Overview

Principles of X-ray Diffraction

Instrument, Sample and Beam Parameters

Selection of the Parameters for the Acquisition

Acquisition and Analysis

Results

Applications

Summary

The Atomic Theory of Matter

The earliest recorded discussion of the basic structure of matter comes from ancient Greek philosophers. Leucippus and Democritus argued that all matter ...

Subatomic Particles

Dalton was only partially correct about the particles that make up matter. All matter is composed of atoms, and atoms are composed of three smaller ...

Elements: Chemical Symbols and Isotopes

A chemical symbol is an abbreviation used to indicate an element or an atom of an element. For example, the symbol for mercury is Hg. The same symbol is ...

Atomic Mass

Atoms &mdash; and the protons, neutrons, and electrons that compose them &mdash; are extremely small. For example, a carbon atom weighs less than 2 ...

physical-properties-of-minerals-ii-polymineralic-analysis

Physical Properties Of Minerals II: Polymineralic Analysis

Source: Laboratory of Alan Lester - University of Colorado Boulder
The physical properties of minerals include various measurable and discernible ...

physical-properties-of-minerals-i-crystals-and-cleavage

Physical Properties Of Minerals I: Crystals and Cleavage

Source: Laboratory of Alan Lester - University of Colorado Boulder
The physical properties of minerals comprise various measurable and discernible ...

Atoms and elements

Content elaboration: This unit builds upon the Earth and Space Science strand in grade 6, where common minerals are defined, tested and classified. It also incorporates knowledge of mineral properties and crystalline structures (chemical compositions and bonding) included in the chemistry sections of other high school courses. The emphasis in this course is to relate the chemical and physical components of minerals to the properties of the minerals. This requires extensive mineral testing, investigations, experimentation, observation, use of technology and models/modeling. The focus is on learning the ways to research, test and evaluate minerals, not in memorization of mineral names or types. Properties such as cleavage and hardness are connected to the chemical structure and bonding of the mineral. In addition, the environment in which minerals form should be part of the classification of the mineral, using mineral data to help interpret the environmental conditions that existed during the formation of the mineral.

Atoms and elements

Types of Chemical Bonds

Chemical bonding theories were pioneered by American chemist Gilbert&#xA0;N. Lewis. He developed a model called the Lewis model to explain the type and ...

Ionic Bonds

When atoms gain or lose electrons to achieve a more stable electron configuration they form ions. Ionic bonds are electrostatic attractions between ions ...

Ionic Bonding and Electron Transfer

Ions are atoms or molecules bearing an electrical charge. A cation (a positive ion) forms when a neutral atom loses one or more electrons from its valence ...

Lewis Symbols and the Octet Rule

Chemical bonds are complex interactions between two or more atoms or ions, which reduce the potential energy of the molecule. Gilbert N. Lewis developed a ...

Chemical Bonds


Atoms participate in a chemical bond formation&#160;to acquire a completed valence-shell electron configuration similar to that of the noble gas nearest ...

Covalent Bonding and Lewis Structures

Compared to ionic bonds, which results from the transfer of electrons between metallic and nonmetallic atoms, covalent bonds result from the mutual ...

Bonding in Metals

Metallic bonds are formed between two metal atoms. A simplified model to describe metallic bonding has been developed by Paul Dr&#xFC;de called the ...

soil-nutrient-analysis-nitrogen-phosphorus-and-potassium

Soil Nutrient Analysis: Nitrogen, Phosphorus, and Potassium

Source: Laboratories of Margaret Workman and Kimberly Frye - Depaul University
In this experiment, three soil macronutrients are chemically extracted, ...

Chemical bonding (ionic, covalent, metallic)

Content elaboration: This unit builds upon the Earth and Space Science strand in grade 6, where common minerals are defined, tested and classified. It also incorporates knowledge of mineral properties and crystalline structures (chemical compositions and bonding) included in the chemistry sections of other high school courses. The emphasis in this course is to relate the chemical and physical components of minerals to the properties of the minerals. This requires extensive mineral testing, investigations, experimentation, observation, use of technology and models/modeling. The focus is on learning the ways to research, test and evaluate minerals, not in memorization of mineral names or types. Properties such as cleavage and hardness are connected to the chemical structure and bonding of the mineral. In addition, the environment in which minerals form should be part of the classification of the mineral, using mineral data to help interpret the environmental conditions that existed during the formation of the mineral.

Chemical bonding (ionic, covalent, metallic)

Structures of Solids

Solids in which the atoms, ions, or molecules are arranged in a definite repeating pattern are known as crystalline solids. Metals and ionic compounds ...

Ionic Crystal Structures

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 ...

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, ...

Classifying Matter by Composition

Matter: Pure Substances and Mixtures
According to its composition, the matter can be classified into two broad categories &mdash; pure substances and ...

Optical Materialography Part 2: Image Analysis

Source: Faisal Alamgir, School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA
The imaging of microscopic structures of ...

X-ray Photoelectron Spectroscopy

Source: Faisal Alamgir, School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA
X-ray photoelectron spectroscopy (XPS) ...

Crystallinity (crystal structure)

Content elaboration: This unit builds upon the Earth and Space Science strand in grade 6, where common minerals are defined, tested and classified. It also incorporates knowledge of mineral properties and crystalline structures (chemical compositions and bonding) included in the chemistry sections of other high school courses. The emphasis in this course is to relate the chemical and physical components of minerals to the properties of the minerals. This requires extensive mineral testing, investigations, experimentation, observation, use of technology and models/modeling. The focus is on learning the ways to research, test and evaluate minerals, not in memorization of mineral names or types. Properties such as cleavage and hardness are connected to the chemical structure and bonding of the mineral. In addition, the environment in which minerals form should be part of the classification of the mineral, using mineral data to help interpret the environmental conditions that existed during the formation of the mineral.

single-crystal-and-powder-x-ray-diffraction

Single Crystal and Powder X-ray Diffraction

Source: Tamara M. Powers, Department of Chemistry, Texas A&#38;M University&#160;
X-ray crystallography is a technique that uses X-rays to study the ...

determining-the-solubility-rules-of-ionic-compounds

Determining the Solubility Rules of Ionic Compounds

Source: Laboratory of Dr. Neal Abrams &#8212; SUNY College of Environmental Science and Forestry
An ionic compound&#39;s solubility can be determined via ...

Criteria of a mineral (crystalline solid, occurs in nature, inorganic, defined chemical composition)

Content elaboration: This unit builds upon the Earth and Space Science strand in grade 6, where common minerals are defined, tested and classified. It also incorporates knowledge of mineral properties and crystalline structures (chemical compositions and bonding) included in the chemistry sections of other high school courses. The emphasis in this course is to relate the chemical and physical components of minerals to the properties of the minerals. This requires extensive mineral testing, investigations, experimentation, observation, use of technology and models/modeling. The focus is on learning the ways to research, test and evaluate minerals, not in memorization of mineral names or types. Properties such as cleavage and hardness are connected to the chemical structure and bonding of the mineral. In addition, the environment in which minerals form should be part of the classification of the mineral, using mineral data to help interpret the environmental conditions that existed during the formation of the mineral.

physical-and-chemical-properties-of-matter

Physical and Chemical Properties of Matter

The characteristics that enable us to distinguish one substance from another are called properties.

Physical Properties of Matter

A physical property is ...

Metallic Solids

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 ...

Properties of Transition Metals

Transition metals are defined as those elements that have partially filled d orbitals. As shown in Figure 1, the d-block elements in groups 3&#8211;12 are ...

stress-strain-characteristics-of-aluminum

Stress-Strain Characteristics of Aluminum

Source:&#160;Roberto Leon, Department of Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA
Aluminum is one of the most abundant materials ...

an-overview-of-bgdgt-biomarker-analysis-for-paleoclimatology

An Overview of bGDGT Biomarker Analysis for Paleoclimatology

Source: Laboratory of Jeff Salacup&#160;- University of Massachusetts Amherst
Throughout this series of videos, natural samples were extracted and ...

an-overview-of-alkenone-biomarker-analysis-for-paleothermometry

An Overview of Alkenone Biomarker Analysis for Paleothermometry

Properties of minerals (hardness, luster, cleavage, streak, crystal shape, fluorescence, flammability, density/specific gravity, malleability)

Content elaboration: This unit builds upon the Earth and Space Science strand in grade 6, where common minerals are defined, tested and classified. It also incorporates knowledge of mineral properties and crystalline structures (chemical compositions and bonding) included in the chemistry sections of other high school courses. The emphasis in this course is to relate the chemical and physical components of minerals to the properties of the minerals. This requires extensive mineral testing, investigations, experimentation, observation, use of technology and models/modeling. The focus is on learning the ways to research, test and evaluate minerals, not in memorization of mineral names or types. Properties such as cleavage and hardness are connected to the chemical structure and bonding of the mineral. In addition, the environment in which minerals form should be part of the classification of the mineral, using mineral data to help interpret the environmental conditions that existed during the formation of the mineral.

properties-minerals-hardness-luster-cleavage-streak-crystal-shape

Properties of minerals (hardness, luster, cleavage, streak, crystal shape, fluorescence, flammability, density/specific gravity, malleability)

Crystal Structure Using X-ray Diffraction

Description

Transcript

Tags

More videos by Standards