Purchase of X-ray powder diffractometer

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We are requesting funds to purchase another X-ray powder diffractometer. In the short term, our capability to acquire data will significantly increase with two instruments, and in the long term, we will have the security of a backup instrument as the old one becomes increasingly unreliable. The principles of a powder diffraction are as follows. The relationship between X-ray wavelength, diffraction angle, and the spacing of planes of atoms in crystals is simple. Using a diffractometer, knowledge of the first two allows measurement of the latter. Two basic types of information can be obtained from the peaks in a powder diffraction pattern: (i) the peak positions are a function of the size and symmetry of the unit cell, and (ii) the peak intensities are a function of the types and arrangement of atoms in the unit cell. From these data we can identify the crystalline phases present in a powder, calculate the dimensions of the unit cells, assess the degree of strain in the structure, and determine the average crystallite size of all the phases contributing to the diffraction pattern. In addition, using the Rietveld method, we can accurately and precisely measure the relative abundances of all the phases present, including amorphous material. Such measurements are of crucial importance to mineralogy, petrology and the materials sciences in general. X-ray powder diffraction is an essential tool for the following projects: application of the Rietveld method to identify and measure the abundance of minerals in diverse geological, industrial and environmentally unfriendly materials, prediction of environmental impacts of mining activities such as acid-rock drainage, sequestration of anthropogenic CO2 in mine tailings, determining the structures of minerals that are presently unknown, the structural characterization of novel nanomaterials, alloys and ceramics, and to identify and characterize new catalysts relevant to Canada's natural gas and heavy oil processing industries. This instrument will allow the Electron-Microbeam/X-Ray Diffraction Facility at UBC to significantly improve the quantity, quality and stability of our services to researchers, and to the minerals and materials industry in Canada.