X-ray absorption factor

The X-ray absorption factor (A) counts the decrease in density of characteristic X-rays from emitting location to detector. The absorption follows an exponential relationship as shown in Equation 2.2. 

Paalman HH, Pings CJ (1962) Numerical evaluation of X-ray absorption Factors for cyhndri-cal samples and annular samples cells. J Appl Phys 33(8) 2635-2639... 

Quantitative analysis of phase in the multi-phase system has always been a problem. Although the XRD is the most studied technique in the past as quantitative analysis of phase, but because multicrystalline XRD has problems of bulk effect of different X-ray absorption factors, the peak-overlap and changes in the intensity of diffraction hkl is caused by difference of fine structure which cannot be solved by traditional method. Thus, the results are always unsatisfied and considered to be unreliable. Rietveld analysis has completely solved the problem. The basic equation is ... 

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