A POWDER DIFFRACTION PHASE IDENTIFICATION ALGORITHM

Within the tolerance range of d values of a diffraction peak, the peak intensity can arise from more than one phase, and a suitable algorith m is essential to correctly calculate the relative intensity I/I-1 of a diffraction peak. In the present algorithm an equation is formed for each diffraction peak in the form: Id(1)X(1) + I(d2)X(2) + ... + I(dn )X(n) = Y-d where d and n denote the dth peak and the n(th) phase. The value of the total intensity of the d(th) diffraction peak, Y-d, is m easured from the diffractogram while the values of I-dn are provided i n the Powder Diffraction File as the standard relative intensity. The relative intensity of each experimental peak for a phase is calculated using the set of equations arising from the diffraction peaks, and th us not only the d but also the corresponding relative intensity I/I-1 values of the unknown phases can be matched.