So far, the world has failed to deliver the actions necessary to meet the climate targets agreed upon at the Paris meetings in 2015. Consequently, it will be necessary to remove carbon from the atmosphere and achieve so called negative emissions. Chemical-Looping combustion (CLC) utilizes oxygen carriers to transfer oxygen from air to fuel for heat, power, and chemical production. When utilized for combustion, no equipment or energy is required to obtain CO2 in pure form. Thus, when using biomass with CLC, negative emissions of CO2 can be achieved at low cost. The cornerstone of the CLC technology are the oxygen carrier particles which need to be sufficiently reactive with fuel while at the same time having high resistance towards attrition over many redox cycles. The development of these particles benefits from having theoretical estimates of the chemical properties of said particles before attempting to synthesize them. These estimates can be obtained by using computational methods based on crystal structures and phonon calculations. The main goal of the project is to set up atomistic-based models that generate energetics of many mixed or combined metal oxides of relevance for the role of an oxygen carrier in a CLC system. The project combines new experimental and modelling endeavors with research in existing experimental infrastructure. The presentation/poster will present the methodology and most current findings of the project, which includes theoretical estimates of the thermal properties of perovskites such as CaMnO3 based on proven computational methods.