Organic electronic devices consist of amorphous or crystalline organic semiconducting materials. These materials are used in light-emitting devices (OLEDs) for display and lighting technology as well as in organic photovoltaics (OPV). A limiting factor in OLED devices in general is the relatively short lifetime, which is reflected in an overall decrease of the electroluminescence and lacking color stability. To develop a comprehensive model of OLED degradation, it is necessary to study the charge and exciton transport in multi-stack device architecture. In amorphous organic semiconductors, charge transport is modeled as a sequence of hopping processes where hopping rates are obtained from quantum mechanical calculations (see project 2 website) and the propagation of individual electrons/holes or excitons through the device is simulated using a kinetic Monte-Carlo method. We represent the amorphous solid as a hopping matrix where each individual site represents a host or guest molecule and all possible hopping processes are associated with a certain rate (see figure). Based on kMC simulations, device properties such as internal quantum efficiencies, current-voltage characteristics and other material and device-specific properties can be obtained.