Element six times larger than chromium?

Quantum mechanics do not give atoms a fixed size, since there are excited states which make electrons jump into a higher orbital and eventually might ionize the atom. However, the closest thing is "Element six times more atomic radius than chromium" which would be an element with 840 pm (10*10^-12 meters) that is not to be discovered quite yet, or so since osmium is only 840 kJ/mol in ionization energy. Make sure the units are the same.

Osmium only has an empirical atomic radius of 185 pm, and chromium's empirical atomic radius is 160 pm.