Topological Analyses of Charge Densities in Ionic Crystals and Crystal Radii

2 Topological Analyses of Charge Densities in Ionic Crystals and Crystal Radii  

When publishing his tables of effective ionic radii. Shannon referred to the results of the charge density studies and included a second table of crystal radii where the radius of each cation had been increased by addition of 14 pm and the radius of each anion reduced by the same amount. It should be clear that addition of the crystal radii of the cation and anion will produce the same interatomic distance as addition of the traditional effective ionic radii, but Shannon felt that crystal radii correspond more closely to the physical size of the ions in a solid.  

More recently Tsirilson and coworkers have reported the results of highly accurate AIM charge density studies of NaF and the isomorphic MgO [45]. The cation-hcp and anion-hcp distances in NaF are 106 and 126 pm, respectively, whereas in MgO they are 92 and 119 pm, respectively. If these amon-bcp distances 

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