The aggregates of a protein called, Axcexb2 found in brains of Alzheimers patients are strongly believed to be the cause for neuronal death and cognitive decline. Among the different forms of Axcexb2 aggregates, smaller aggregates called soluble oligomers are increasingly believed to be the primary neurotoxic species responsible for early synaptic dysfunction. Since it is well known that the Axcexb2 aggregation is a nucleation dependent process, it is widely believed that the toxic oligomers are intermediates to fibril formation, or what we call the on-pathway products. Modeling of Axcexb2 aggregation has been of intense investigation during the last decade. However, precise understanding of the process, pre-nucleation events in particular, are not yet known. Most of these models are based on curve-fitting and overlook the molecular-level biophysics involved in the aggregation pathway. Hence, such models are not reusable, and fail to predict the system dynamics in the presence of other competing pathways.