The combined nuclei then exhibit the same 1/r force as a single nucleus.

Species with more than a single nucleus can (I think) be defined as molecules.

There are hundreds of mitochondria in a cell, as compared to a single nucleus.

Any thermal energy is shared by the whole lattice rather than a single nucleus.

The most energetic cosmic rays have comparable energy focused on a single nucleus.

Each individual thallus consists of a single cell with a single nucleus.

In this context, a neutron star is effectively a single atomic nucleus.

Not all cells have just a single nucleus.

Atomic models will consist of a single nucleus that may be surrounded by one or more bound electrons.

They can pass through a dozen light-years of lead without bouncing off a single nucleus.