Frisch et al., gaussian 09, Revision D.1, Gaussian, Inc., Wallingford, CT, 2009. Keith, AIMAll (Version 14.11.23), TK Gristmill Software, Overland Park, KS, USA, 2014, . Sodium Facts Sodium Covalent Radius Atomic Number 11 Learn more about the atomic number. Bader, Atoms in Molecules: A Quantum Theory ( Oxford University Press, Oxford, 1990). Since the boundary is not a well-defined physical entity, there are various non-equivalent definitions of atomic radius. We also find that the electron density at the bond critical point increases exponentially as the sodium radius decreases. The atomic radius of a chemical element is a measure of the size of its atom, usually the mean or typical distance from the center of the nucleus to the outermost isolated electron. Atomic Radius: Atomic radius can be calculated as the distance from the nucleus of an atom to its boundary of the electron cloud. Ionic Radius: Ionic radius is the radius of an atom’s ion. Contrary to common wisdom, the water radius is not constant, decreasing even more than that of Na + as the CN decreases. Atomic Radius: Atomic radius is the radius of a neutral atom. We utilize Bader’s theory of atoms in molecules to bisect the Na +–O distances into Na + and water radii.
![sodiums atomic radius sodiums atomic radius](http://boomeria.org/chemtextbook/table10-9.jpg)
This extends the CN dependence of the sodium-water distances from crystal structures (CN = 4–12) to lower CN values, revealing a switch between two power laws, having a small exponent at small CNs and a larger one at large CNs. The bulk limit is obtained by the polarizable continuum model, which acts to increase the interatomic distances at small CN, but has a diminishing effect as the CN increases. Here we adopt a “bottom-up” approach of obtaining these distances from quantum chemistry calculations of gas-phase Na + ( H 2 O ) n clusters, as a function of the sodium coordination number (CN = 2–6). Recent experimental values in solution are notably smaller than those from previous X-ray studies and ab initio molecular dynamics. Yet, in spite of numerous studies, the (average) distance between the sodium cation and its water ligands, and the corresponding ionic radii, are still controversial.
![sodiums atomic radius sodiums atomic radius](https://useruploads.socratic.org/whNw2oHDTxijVKzxU68A_ATRADIID.DIR_PICT0003.gif)
The sodium cation is ubiquitous in aqueous chemistry and biological systems.