Hi all, Sorry, I may be asking a question already asked in the mailing list, but I am unable to get it from the earlier discussions. I am reading one of the research article ´´ Determination of crystallite size in a magnetic nanocomposite using extended x-ray absorption fine structure´´ .J. Appl. Phys,. vol 94, page 778, 2003 In this paper there is a formula N_nano = [1-3/4(r/R)+1/16(r/R)^3]N_bulk, which you said can be used in the Artemis for extracting the particle size. I am trying to use this formula for determination of size of Ni particles in an Ni / Al2O3 catalyst. From TEM the size determined is around 4 nm. So, I am trying to fit the theoretical model of Ni metal to the sample data in the Artemis I defined a guessed parameter R and then put the whole formula for S02 = amp*(1-(0.75*(Reff/R))+(0.063*(Reff*Reff*Reff/(R*R*R)))). The value of R I am getting is 0.81 (0.05) which is quite small. Is there something I am missing in the formula or I have to define the N seprately for sample cooridnation number. Currently, I am using only the first path in the fitting. With thanks Abhijeet Gaur -- *Dr. Abhijeet Gaur* *Post doctoral fellow in the Institute for Chemical Technology and Polymer Chemistry * *Karlsruher Institut für Technologie (KIT), Karlsruhe Germany.*