Need to make a Report Write a report on the XRD device Write an introduction, features and idea of the device and the applications and components of the device Have to include the references

Introduction X-ray diffraction in crystals as in a three-dimensional diffraction grating was first introduced in the meeting conducted by the German Physical Society at the University of Berlin in 1912, by a physicist, Max von Laue. The discovery has solved the problem of the nature of X-rays and the sizes of atoms. Thereafter research works on this topic have improved significantly and new ideas were introduced shortly. W. H. Bragg and W. L. Bragg, who were father and son, used this discovery to confirm Barlow’s hypothetic model of rock salt and thereby initiating the first X-ray diffraction analysis of single crystals. In ancient days, X-ray diffraction studies were conducted manually, but with the advent of digital technologies, all the procedures in X-ray diffraction were automated (Borisov & Podberezskaya, 2012). Nowadays high energy X-ray diffraction techniques are widely used, rather than conventional methods, as the structure factors can be measured out to higher momentum transfers (Q >20 °A-1) at smaller scattering angles, which resulted in higher real space resolution and in the case of small samples attenuation and multiple scattering effects are negligible (Benmore, 2012). Materials science is a branch of science or an interdisciplinary field that deals with the study of the properties of solid materials on the basis of their composition and structures. In the field of materials science, X-ray diffraction (XRD) has become a powerful and common technique, which is widely used, in order to determine the crystallographic structure of materials. XRD is a sensitive analytical method that has been extensively used for the examination of crystalline materials and thin films. It is based on the constructive interference of monochromatic X-rays (which are generated by a cathode ray tube and filtered to produce monochromatic radiation, collimated to concentrate), and the crystalline sample on which the X-rays are finally directed. The intensity and scattering angles of the X-ray which leave the sample material are measured to identify its structure and properties (Bunaciu, Udriştioiu, & Aboul-Enein, 2015). The incident X-rays are scattered by the atoms present in the sample upon interaction with the electrons (scatterer) in the atoms and the process is termed elastic scattering. An array of scatterers produce an array of spherical waves, which are usually cancelled by each other through destructive interferences, but some of them which are scattered in a particular direction are escaped from being cancelled by others and they can be determined by Bragg’s law: nλ = 2d sinθ Where n is an integer, λ is the wavelength of the X-ray, d is the spacing between diffracting planes, and θ is the incident angle (diffraction angle). This law clearly states the relationship between electromagnetic radiation, diffraction angle, and the lattice spacing in the crystalline sample. The uncancelled waves (diffracted X-rays) produce spots on the diffraction pattern and are called reflections. They are first detected, then processed, and finally counted. In order to obtain all the possible diffraction directions of the lattice, the sample is scanned through a range of 2θ angles. Identification of the sample compounds which have unique d-spacings can be achieved by converting the diffraction peaks to d-spacings and comparing them with the d-spacings of standard reference patterns. The shape and size of the unit cell can be determined by the position of the diffraction peak, whereas, atomic number and atomic position can be determined by diffraction peak intensity. Diffraction at small angles occurs when there is a long repeated distance in the atomic arrangement (periodicity), while short repeated distances result in diffraction at high angles (Ameh, 2019). The wavelength of the X-rays has the same order of magnitude as the spacing (d) between the crystal planes, which ranges from 1-100 angstroms, making them a better choice for irradiating the samples (Bunaciu et al., 2015). Components of XRD Device The XRD device is also known as an X-ray diffractometer, which consists of three basic components: an X-ray tube (cathode ray tube), a sample holder, an X-ray detector, and a minicomputer for control, data acquisition, and data processing. The sample rotates in the path of the collimated X-ray beam at an angle θ while the X-ray detector is mounted on an arm to collect the diffracted X-rays and rotates at an angle of 2θ, with the help of a goniometer. The X-ray beams will be passed through the soller slits which are then directed on the samples and the diffracted rays are passed through the divergence slit and receiving slits and collected at the detector film. This geometric arrangement is termed Bragg–Brentano parafocusing system. The amount of divergence is determined by the effective focal width of the source and the aperture of the divergence slit. Axial divergence is controlled by two sets of parallel plate collimators (Soller slits) placed between the focus and specimen and between the specimen and scatter slit, respectively. Use of the narrower divergence slit will result in a smaller specimen coverage at a given diffraction angle, thus lower diffraction angles can be attained, where the specimen has a larger apparent surface (thus larger values of ‘d’ are attainable) (Bunaciu et al., 2015). The X-rays are generated in a cathode ray tube by heating a filament to produce electrons, which are accelerated towards the target (sample) with the help of a current to bombard it. If the electrons have sufficient energy to dislodge the electrons in the inner shells of the sample, characteristic X-ray spectra are formed on the detector film. Applications of XRD XRD plays an important role in the analysis of all kinds of solid crystalline materials, including medications, medicinal preparations, dietary supplements, other organic and inorganic compounds, etc. Being a non-destructive method, it can be used for the identification of unknown compounds, investigation of polymorphism, solvation, and salt form identification, determination of Physico-chemical properties, and detection of impurities and anomalies in the medications (Jendrzejewska, 2020). An interesting study has been conducted and reported that XRD could be used for the elucidation of structural and mechanical properties of mineral crystals in the bone (Tadano & Giri, 2011). It can also be used for the identification of crystalline phases and orientation. Crystal structures can be determined using XRD and are based on the lattice parameters of the unit cell of the crystalline sample like lattice points, the number of atoms per unit cell, packing factor of atoms, and the coordinate number of atoms in the unit cell (Ameh, 2019). It is reported that the surface properties of carbon and graphite could be determined using XRD (Sherwood, 2001). High-energy X-rays are used for the structural elucidation of liquids and glasses (Benmore, 2012). The Solid phase transitions such as polymorph inter-conversions are routinely examined by XRPD (X-ray powder diffraction) using variable temperature sample stages (VT-XRPD). Both sub-ambient and elevated temperature stages are used for this. XRD also has applications in the field of forensics. Here XRD is used mainly in contact trace analysis like paint flakes, hair, glass fragments, soils, stains of any description, and loose powdered materials. Identification and comparison of trace quantities of material can help in the conviction or exoneration of a person suspected of involvement in a crime. XRD is the only analytical method that can provide information about the phase composition of solid materials. Thus they can be used in the corrosion analysis (Bunaciu et al., 2015). Conclusion X-ray diffraction (XRD) is an analytical technique used to characterize crystalline phases of a wide variety of materials, typically for mineralogical analysis and unknown identification. Since it is a non-destructive method, it predominates over other methods. References Ameh, E. S. (2019). A review of basic crystallography and x-ray diffraction applications. International Journal of Advanced Manufacturing Technology, 105(7–8), 3289–3302. https://doi.org/10.1007/s00170-019-04508-1 Benmore, C. J. (2012). A Review of High-Energy X-Ray Diffraction from Glasses and Liquids. ISRN Materials Science, 2012, 1–19. https://doi.org/10.5402/2012/852905 Borisov, S. V., & Podberezskaya, N. V. (2012). X-ray diffraction analysis: A brief history and achievements of the first century. Journal of Structural Chemistry, 53, 1–3. https://doi.org/10.1134/S0022476612070013 Bunaciu, A. A., Udriştioiu, E. gabriela, & Aboul-Enein, H. Y. (2015). X-Ray Diffraction: Instrumentation and Applications. Critical Reviews in Analytical Chemistry, 45(4), 289–299. https://doi.org/10.1080/10408347.2014.949616 Jendrzejewska, I. (2020). Application of X-Ray Powder Diffraction for Analysis of Selected Dietary Supplements Containing Magnesium and Calcium. Frontiers in Chemistry, 8(September), 1–12. https://doi.org/10.3389/fchem.2020.00672 Sherwood, P. M. A. (2001). Carbons and Graphites: Surface Properties of. Encyclopedia of Materials: Science and Technology, 985–995. https://doi.org/10.1016/b0-08-043152-6/00183-2 Tadano, S., & Giri, B. (2011). X-ray diffraction as a promising tool to characterize bone nanocomposites. Science and Technology of Advanced Materials, 12(6), 064708. https://doi.org/10.1088/1468-6996/12/6/064708

Need to make a Report

Get Instant Homework HelpOn Your Mobile

Get Instant Homework HelpOn Your Mobile

Get Instant Homework HelpOn Your Mobile