Definition:Atomic Charge Density

Definition
Let $B$ be a body of matter.

The atomic charge density $\rho_{\text {atomic} }$ of $B$ is the electric charge density within $B$ associated with the atoms that make up $B$.

Hence:
 * inside the nucleus $\rho_{\text {atomic} }$ is high and positive
 * in the electron cloud $\rho_{\text {atomic} }$ is negative.