This resource request is aimed at supporting our ongoing efforts in materials discovery and chemistry under extreme conditions. Currently this research is enabled by a large allocation (SNIC 2021/3-11 600,000 core-h/month), which we wish to downscale to 200,000 core-h/month. We are focused on two topics: (i) predicting pathways leading to astrochemical polymers and co-crystalline materials and (ii) predicting novel properties of materials under high-pressure. The properties we are exploring include, but are not limited to, new polarity inverted bonds and a new transition metal chemistry in alkali and alkali earth elements. To this end, we are screening large numbers of structures and reaction pathways using structure search algorithms and molecular dynamics simulations coupled to quantum chemical methods. Computationally demanding quantum chemical methods are required to obtain accurate predictions of structure, stability, reaction kinetics and thermodynamics.