# Compounds with high electron density [closed]

If $d$ is the ratio of the total number of electrons in a compound and the average radius(of all anions and cations, or covalent radii), are there known compounds (inorganic or organic) where $d$ is high?

Are there any rules or analytic techniques to design such compounds that have stable chemistry?

Please don't confuse the electron density in the title to this one

Edit: Assume the constraint that we want common elements and no exotic, radioactive ones.

• Your d is high where the atomic number is high. – Ivan Neretin Mar 22 '18 at 4:43
• @IvanNeretin: Edited. Consider the effect of average radius as well. – batta Mar 22 '18 at 4:51
• I still stand by my statement. – Ivan Neretin Mar 22 '18 at 5:12