Atomic/Ionic Radius as Mathematical Limit of System Energy Evolution

Abstract

The classical, in its nature, concept of atomic or ionic radii, although profitable in many fields, is represented by an ambiguous choice of formulations. In this work, we propose a definition of atomic and ionic radii rooted in chemical principles and conceptual density functional theories. The estimation based on electron density fundamental response functions has been successfully tested. The generalized approach has been shown to be applicable to atoms in any oxidation state. The radii display good correlation with classical estimates, such as Shannon. The atomic and ionic radii obtained according to this scheme are directly comparable between different elements, without any adjustment procedures requiring fitting constants. The definition also has a clear physical interpretation, which supports understanding of size-related phenomena and trends.

Relating atomic energy, radius and electronegativity through compression

“…One early motivation for attaining atomic and ionic sizes was to help understand X-ray diffraction patterns in terms of crystal structures, 5,6 another to provide a rationalization for metallization. [7][8][9] Today, a variety of definitions of atomic radii with well-known uses exists, including, e.g., ionic, [10][11][12] covalent, 6,[13][14][15][16][17] and vdW radii. 3,[18][19][20][21] Electronegativity is a similarly well-studied concept that can be defined in many ways (see, e.g., 22-29 and references therein).…”

Non‐Bonded Radii of the Atoms Under Compression

“…How large are atoms, a question that has been asked for more than one and a half century? [2] Today, a number of definitions of atomic radii exists, and includes, for example, various ionic, [3–10] covalent, [11–24] vdW, [2,25–33] and other radii [10,34–44] …”

Effect of glass composition on the physical properties and luminescence of Pr3+ ion‐doped chalcogenide glasses

“…Table 1 summarizes that iodine reduces the T g of the glass. The ionic polarizability is higher in Sb than in In and Ga. 29 A high ionic polarizability leads to an increase in the degree of ion polarization in the glass. These effects can reduce the connectivity of the glass network, and therefore account for the decrease in T g with the increase in I addition Ge 20 Ga 5 Sb 10 Se 65 glass.…”

“…Therefore, Sb is more easily polarized than Ga and In. The ionic polarizability is higher in Sb than in In and Ga. 29 A high ionic polarizability leads to an increase in the degree of ion polarization in the glass. Furthermore, the atomic mass is higher in Sb (121.8) than in In (114.8) and Ga (69.72).…”