A Study of the Atomic Ordering in the Niobium Carbide Using the Magnetic Susceptibility Method

The magnetic susceptibility of a nonstoichiometric niobium carbide in the ordered and disordered state in the region of homogeneity of the Nb6, C5, phase is measured. It is for the first time that the magnetic susceptibility method is employed to analyse the atomic distribution in the crystal and to determine the short-range order parameters. In terms of the cluster approach proposed, a short-range parameter calculation is carried out which shows that the variation of the magnetic susceptibility due to ordering in the niobium carbide is associated with, chiefly, the formation of short- range order rather than with the formation of long-range order. A considerable increase in the diamagnetism of an ordered niobium carbide compared to that of a disordered one is noted. [Russian Text Ignored].