is The "Beta" (β) same the FWHM in the Scherrer formula to calculate the crystallite average size in the profile of Gaussian, Pseudo-Voigt, Pearson VII, Lorentzian?
X-ray Diffraction Fundamentals:
- http://pd.chem.ucl.ac.uk/pdnn/peaks/peakcon.htm
- http://pd.chem.ucl.ac.uk/pdnn/pdindex.htm#peaks
For a Gaussian profile, for example, "the integral breadth, β, is related to the FWHM peak width, H, by β = 0.5 H (π / loge2)1/2.
The most important features of the Gaussian function are:
- that it is easy to calculate
- it is a familiar and well-understood function
- it is a good function to describe both neutron and energy-dispersive X-ray powder diffraction peaks (it is however not good at describing angle-dispersive X-ray diffraction peaks)
- it has a convenient convolution property
- it is symmetrical"
In practice one would have to use a "known standard" to determine the "instrumental profile" :-)
Numerically, it is a lot easier to compute the "integral breadth" by computing the integrated intensity and then dividing it by the Imax after considering the monotonous background and accounting for any preferred orientation effects.
http://web.pdx.edu/~pmoeck/phy381/Topic5a-XRD.pdf
http://pd.chem.ucl.ac.uk/pdnn/peaks/peakcon.htm
http://pd.chem.ucl.ac.uk/pdnn/pdindex.htm#peaks
Abbas! Why don't you include some of the relevant topics (up to 15) as in the attached example RG question instead of just "Calculations"?
https://www.researchgate.net/post/What_is_the_best_way_to_interpret_REAL_TIME_3D_X_Y_o-2TH_o_ph_ch_reciprocal_space_relative_intensity_data_from_HRXRD_rocking_curve_analyses
- Badges
- Science topic
- Similar topics
- Applied Mathematics
- Calculations