Quantitative analysis Mossbauer spectra

For speetroseopie analysis (e.g. XRF, XRD, IR, Raman, Mossbauer etc.), a plot of the observed intensity versus the eorresponding wavelength or frequeney (or some other related parameter) is ealled the spectrum of that particular analytical method. The spectrum or the data obtained from such experiments contain information about nature of the interactions, atomic and molecular energy levels, chemical bonds, crystallographic information and other related processes. When only the item of interest is identified, it is called qualitative analysis and when the amoimt present is estimated, it is known as quantitative analysis. The effect of heat on a sample is reflected through its variation of thermodynamic properties. Such studies are done by thermal analysis. 

A variety of spectroscopic techniques, however, are of value to determine the local bonding and, occasionally, oxidation states of various ions. Frequently, they can perform satisfactory quantitative analysis or estimates as well. Adsorption, emission, and Raman spectroscopy operating from the UV through the IR region of the spectrum can provide such information. These optical spectroscopies can be performed in either a transmission or surface-scattering mode based on the thickness and absorption properties of the specific sample. Nuclear magnetic resonance (NMR), Mossbauer spectroscopy, and electron spin resonance techniques are some other forms of spectroscopy frequently used to determine local bonding and oxidation states of specific species, primarily in the bulk rather than on the surface. These methods are limited to particular atoms or ions and are not universally applicable. 

Quantitative analysis could be used to measure the concentration of the element component in a sample as well as to identify the oxidation state and phase. In a study by Korecz et al., the Mossbauer spectrum is used to follow, quantitatively, the course of incorporation of iron into the corundum lattice. The composition of the iron aluminium oxide formed was also found to be FeAlsOig, which means an aluminium oxide polymer with an iron atom in every five aluminium atoms. ... 

In general, a Mossbauer spectrum shows different components if the probe atoms are located at lattice positions that are chemically or crystallographically nonequivalent. For instance, from the parameters that characterise a particular Mdssbauer subspectrum, it is possible to establish whether the corresponding probe atoms reside in sites that are not affected by structural lattice defects, or whether they are located at defect-correlated positions. Each compound or phase that contains iron has characteristic parameters in its Mossabauer spectrum. This means that the method is suitable for quantitative as well as qualitative analysis. Mossbauer spectroscopy is also non-destructive and requires only relatively small quantities of samples (- 100mg) [169-171,196-198]. 

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