2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/19362In the work the analysis of crystal chemical researches of nickel borocarbides RNi2B2C (R = rare earth) is given. The reasons of representation of dependence of Tc from crystal chemical parameters by two separate curves for magnetic and nonmagnetic R are considered. Common for all R dependences of Tc from crystal chemical parameters similar existing in layered quasi-two-dimensional systems (HTSC cuprates and diborides) are established. The absence of influence on borocarbides Tc of magnetic properties R is determined. On the basis of the found correlations the radii of a number of rare earths are precised and Tc of compounds at various substitutions R are calculated.17 pages, 6 figures, 4 tableSuperconductivityMaterials Sciencetext