Defect assisted electron transfer processes in metal-oxide materials play a key role in a diverse range of effects of relevance to microelectronic applications. However, extracting the key parameters governing such processes experimentally is a challenging problem. Here, we present a first principles based investigation into electron transfer between oxygen vacancy defects in the high-k dielectric material HfO2. By calculating electron transfer parameters for defects separated by up to 15Å we show that there is a crossover from coherent to incoherent electron transfer at about 5Å. These results can provide invaluable input into numerical simulations of electron transfer, which can be used to model and understand important effects such as trap-assisted tunneling in advanced logic and memory devices. 
First principles modeling of electron tunneling between defects in m-HfO2