Chlorine ionic crystal radius

Bromine has an ionic radius of 1.96 A and thus easily substitutes for chlorine (1.81 A) in the halite crystal lattice as well as in the other chloride salts. The distribution coefficients for bromine in chloride salts deposited from seawater is less than 1 (Warren 2006). 

The ionic radius of chlorine has the value 1.81 A (Chap. 13). The following distances between chlorine atoms of different molecules have been observed in the molecular crystal 1,2,3,4,5,(Whexachlorocyclo-hexane.-57 3,60, 3.77, 3.82 A these are close to twice the ionic radius. Similar agreement is shown by many other organic crystals and inorganic covalent crystals. Cadmium chloride, for example, consists of... 

The relatively small radius of F", 1.19 A, is almost identical with that of the oxide, O2-, ion (1.25 A) consequently, many fluorides and oxides are ionic with similar formulae and crystal structures, for example, CaO and NaF. The compounds of the other halogens with the same formula usually form quite different lattices and may even give molecular lattices. Thus chlorides and other halides often resemble sulfides, just as the fluorides often resemble oxides. In several cases the fluorides are completely ionic, whereas the other halides are covalent for example, CdF2 and SrF2 have the CaF2 lattice (nearly all difluorides have the fluorite or rutile structure), but CdCl2 and MgCl2 have layer lattices with the metal atoms octahedrally surrounded - by chlorine atoms.-----------------------------... 

In making drawings of atoms or molecules, the van der Waals radii may be used in indicating the volume within which the electrons are largely contained. For ions, the ionic radii (crystal radii) discussed in Section 6-10 may be used. The van der Waals radius of an atom and the ionic radius of its negative ion are essentially the same. For example, the van der Waals radius of chlorine is 180 pm, and the ionic radius of the chloride ion is 181 pm. 

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