The relative intensities of partial spectral doublets A, B and C, corresponding to three distinct values of q.s., could be referred to three definite atomic configurations Fe  (Fe _{n} Zn _{12n} ), just if the Fe^{2+} and Zn ions are distributed random. When one takes into account, that the symmetric pairs of Zn ions do not disturb the electric field gradient at the central Fe^{2+} ion, the Cdoublet is to be referred to n_{eff} = 0, B doublet  to n_{eff} = 1 and A doublet to  n_{eff} = 2 or more.
The values of q.s. of doublets A, B and C are changing
with composition a little, the isomer shift has the constant value for all doublets and does not depend on the composition. The data presented, at first prove the random distribution of Fe^{2+} and Zn^{2+} ions in the sphalerite solid solution Fe_{x}Zn_{1x}S, at least up to x = 0.32.
