Structural characteristics of d-elements dioxides (MeO2) belonging to 4-7 groups of the periodic table

According to the model equations for effective ionic radii and crystal structure metamorphosis the structural characteristics of MeO2 (Ті, Nb, Та, Cr, Mn) dioxides tetragonal lattices have been calculated (Me-O interstructural distances, O2- effective radii in dioxides), from the X-ray parameters. The calculated Me4+ radii agree with those obtained earlier from the lattice parameters of cubic singony compounds (halides, carbides, suicides).