Solid phase analysis mineral composition study

Applications The general applications of XRD comprise routine phase identification, quantitative analysis, compositional studies of crystalline solid compounds, texture and residual stress analysis, high-and low-temperature studies, low-angle analysis, films, etc. Single-crystal X-ray diffraction has been used for detailed structural analysis of many pure polymer additives (antioxidants, flame retardants, plasticisers, fillers, pigments and dyes, etc.) and for conformational analysis. A variety of analytical techniques are used to identify and classify different crystal polymorphs, notably XRD, microscopy, DSC, FTIR and NIRS. A comprehensive review of the analytical techniques employed for the analysis of polymorphs has been compiled [324]. The Rietveld method has been used to model a mineral-filled PPS compound [325]. 

Finally, it is clear that many more solid solutions must be examined for minerals and mineral analogs in order to achieve a fundamental understanding of compositionally induced phase transitions. Currently it is not possible to predict how transition temperatures will change when a particular impurity substitutes in a mineral structure, nor can we predict the interaction length for that impurity in the mineral. Landau-Ginzburg analysis provides an ideal framework for comparing the character of phase transitions that are activated by different variables (temperature, pressure, composition), and future studies of this type will lay an empirical foundation from which the detailed character of morphotropic transitions in minerals may be inferred. 

Nondestructive analysis of various materials, such as rocks, composite materials, phases and inclusions in solids, can be performed with a laser molecular microprobe [9.28], which is based on a combination of an optical microscope with a Raman spectrometer. The laser beam is focused into the sample and the Raman spectrum, emitted from the small focal spot, is monitored through the microscope. The principal modes of operation were illustrated by studying the different phases of "fluid inclusions" contained in a quartz crystal from the Swiss Alps. The Raman spectra obtained permit determination of CO2 as a gaseous inclusion, water as liquid inclusion, and the fact that the mineral, thought to be CaSO, is in fact CaCO. ... 

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