We study the equilibrium sediment of a multicomponent system of charged colloids using primitive model
Monte Carlo simulations, which include counterions explicitly. We find separation of the different colloidal
components into almost pure layers, where colloids with large charge-to-mass ratio sediment higher in the
sample. This effect appears due to a competition between ionic entropy, gravitational energy, and electrostatic
energy. Our simulations provide a direct confirmation of recent theoretical predictions on the sedimentation of
multicomponent mixtures of charged colloids in regimes with relatively low total densities and low colloidal
charges. To explore the limitations of the theory we perform simulations at higher total densities for monodisperse
and multicomponent systems and at stronger electrostatic couplings by increasing the colloidal charge for
monodisperse suspensions. We find good agreement between theory and simulation when the colloidal charge
is increased in the monodisperse case. However, we find deviations between simulations and theory upon
increasing the total densities in the monodisperse and multicomponent systems. The density profiles obtained
from simulations are more homogeneous than those predicted by theory. The spontaneous formation of layered
structures predicted by the theory and found by simulation can serve as a useful tool to separate different
components from a mixture of charged colloids
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