What are negatively charged particles found outside of the nucleus?
Electrons That have a negative charge and almost no mass.
Electrons are found in orbitals that are locations of probability for the location of the electrons in specific mathematical shapes around the outside of the nucleus.
The electrons occupy space because of the rapid motion of the electrons around the nucleus. It is beyond amazing how electrons behave. When there are two slits that electrons can go through, the electrons go through both as the same time. How one single electron can go through two silts at the same time means that movement of electrons is outside of and beyond time.
The movement of electrons around the atom occupy more than 99% of the space or volume of the atom. The energy of the electrons creates a "force field" that occupies the space around the atom.