# Silver in defect chemistry

When talking about conductivity in combination with lattice defects you can often see that AgX is taken as an example for a Frenkel defect where the $$\ce{Ag^+}$$ moves to intersticial voids. I remember that my professor once called this a property of silver, that silver likes itself so much that it can be close to other silver cations. And I think we see trends like this in for example $$\ce{Hg2}$$-dimers. Is this some sort of relativistic effect or can I explain it with certain orbitals overlapping that I can get a quite close contact for two $$\ce{Ag^+}$$ ions?