Colloidal Suspensions

Dear Mr. Lane
Sorry to disturb you. But I am trying to simulate a colloidal suspension in lammps, but so far I havent got any sucess. I am following the approach mentioned in

I have to carry out my simulations at different volume fractions and I want to use the atom style sphere. The diameter of the spheres are 10sigma , sigma being 1.

The nature of the errors I am facing are

Large/Large overlap (which disappears when I increase the box size but my volume fractions settings get disturbed )

Also I am setting the diameter as 10 but upon checking the radius in the dump file I find the value 0.5 written there.

compute volP all property/atom radius

this is the compute I am using for finding the atom radius

Any help would be greatly appreciated