How The Aggregation Of Oxygen Vacancies In Rutile-Based Tio2-Delta Phases Causes Memristive Behavior

The results of a comprehensive and systematic ab initio based ground-state search for the structural arrangement of oxygen vacancies in rutile phase TiO2 provide new insights into their memristive properties. We find that O vacancies tend to form planar arrangements which relax into structures exhibiting metallic behavior. These metastable arrangements are structurally akin to, yet distinguishable from, the Magneli phase. They exhibit a more pronounced metallic nature but are energetically less favorable. Our results confirm a clear structure-property relationship between segregated oxygen vacancy arrangement and metallic behavior in reduced oxides.