The basis on which values may be assigned to the radii of ions in crystals is examined. A set of radii in terms of one undetermined parameter (Li+, 2.581–δ; Na+, 2.851–δ; K+, 3.162–δ; Rb+, 3.302–δ; F–,δ–0.520; Cl–, δ–0.020; Br–, δ+0.141; I–, δ+0.399)...
In sodium chloride, a sodium atom (Na) donates an electron to a chlorine atom (Cl), forming an ionic bond. ionic bond n. A chemical bond between two ions with opposite charges, characteristic of salts. Also calledelectrovalent bond. ...
In agreement with these prior studies, the smaller transition metal ions (Co and Ni) naturally adopt the Na2M(SO4)(2) (2-1-2) structure, while the larger transition metal ions (Fe and Mn) adopt the alluaudite-type structure. By exploiting the ion size design relationship, an Fe-...
8.3: Ionic Radii Ionic radius is the measure used to describe the size of an ion. A cation always has fewer electrons and the same number of protons as the parent atom; it is smaller than the atom from which it is derived. For example, the covalent radius of an aluminum atom (1s22s...
Internuclear separations calculated from empirical soft-sphere radii for seventeen crystalline Group 1 halides with rock-salt structures and from empirical hovering-sphere radii for fourteen gaseous Group 1 halide ion-pairs agree well with experimental measurements. Two lithium and four fluoride ion-pairs...
of the ionic radii deviates from the ideal value (T ≠ 1), a geometric strain and crystal distortions arise. As the deviation fromT = 1 becomes greater, the crystal adopts structures of lower symmetry than the cubic one. Thus by calculatingT, the crystalline structure can be ...
Factors which affect radii additivity are polyhedral distortion, partial occupancy of cation sites, covalence, and metallic character. Mean Nb5+-O and Mo6+-O octahedral distances are linearly dependent on distortion. A decrease in cation occupancy increases mean Li+-O, Na+-O, and Ag+-O ...
decreasing the radius. Ionic Radii 0 0.05 0.1 0.15 0.2 0.25 0.3 1 2 3 4 5 6 7 8 Element (atomic number) R a d i u s ( n m ) Series1 Na +1 Mg +2 Al +3 14 15 16 17 Si +4 Si -4 P -3 S -2 Cl -1 The ionic radius is the radius of an atom’s ion. Starting ...
A computer simulation technique has been applied to solve the Nernst-Planck equations for the kinetics of exchange of alkali metal ions (Li+, Na+ and K+). Activation energy and the self diffusion coefficient were found to be linear functions of hydration energies and the ionic radii of these...
In the latter case, particle radii ranging from 1.65 to 1.95 nm were found with increasing concentrations up to 3000 mM. Goodchild et al. reported a particle radius of 1.34 nm and 1.05 nm for [C10mim]Br and [C8mim]Br respectively, and in both cases their shape shifted from spherical to...