Light simulation for nEXO

nEXO is a tonne scale liquid xenon time projection chamber (TPC) that aims to detect neutrinoless double beta decay in ¹³⁶Xe with a projected 90 % CL sensitivity of 1.35 x 10²⁸ yr. nEXO will be able to measure energy deposits from both ionization electrons and scintillation photons from events that occur inside the detector. Silicon photomultiplers will surround the sides of the TPC to detect scintillation light, providing a more highly pixellated light collection system than previous liquid Xe TPCs. With this design, the detector will have high light collection efficiency and energy resolution of σ/Q_ββ < 1% with low amounts of plastic as well as the ability to image the location of interactions based on their light signals. This talk presents the simulation of the light response in the nEXO detector and its impact on the experiment's sensitivity along with possible future background reduction through the use of light based position reconstruction in the experiment.