This proposal brings together a consortium of partners to create a national Tier 2 Hub for materials and molecular modelling (MMM). Materials have an enormous impact on the UK economy: according to the former Minister of State for Universities and Science, UK businesses that produce and process materials have a turnover of around £170 billion per annum and represent 15% of UK GDP. At the heart of almost every modern technology, including energy generation, storage and supply, transportation, electronic devices, defence and security, healthcare, and the environment, it is materials that place practical limits on efficiency, reliability and cost. MMM is an inherently interdisciplinary 'field' of physicists, chemists, engineers, materials scientists, biologists, geologists, and more who use HPC to enable transformative discoveries of importance to science and industry. The predictive capability of MMM has increased significantly in recent years. MMM can provide fundamental insights into the processes and mechanisms that underlie physical phenomena and has become an indispensable element of contemporary materials research. It is no exaggeration to state that MMM is changing how new materials-based technologies are developed, acting as a guide for experimental research, helping to speed up progress and save resources. It is a rapidly expanding field and one in which the UK has consistently been world-leading. The rapid growth of the field has created an unprecedented need for HPC, particularly for medium-sized high-capacity simulations for which many materials science codes are well-optimised. This Hub will support and enable the MMM community at a time when the ARCHER Tier 1 service is under increasing pressure owing to the success of EPSRC in fostering the growth of HPC research. The establishment of a Tier 2 Hub for MMM will rebalance the ecosystem for this key engineering and physical sciences community, facilitating effective use of the appropriate system to speed up the time to science. It will be strongly integrated with the ARCHER Tier 1 service, optimising the value and impact delivered by ARCHER by enabling a greater concentration of capability jobs. The Hub will leverage the design of UCL's Grace HPC facility to ensure efficient, reliable and timely delivery, with ease of access and use being of paramount importance. The UCL Research Computing Group has considerable experience in HPC and in supporting codes and applications used by the MMM community, in professional IT service delivery, and in collaborative working through membership of e.g. the Science and Engineering South Consortium. Strategies for working with ARCHER, its relevant high-end computing (HEC) consortia, other possible Tier 2 facilities, Centres for Doctoral Training, the Sir Henry Royce Institute, the UK Catalysis Hub, and other computational networks have been identified. This will ensure that the Materials Hub complements and enhances the national e-research landscape, leveraging other substantial UK investments in MMM-related research. We will build on the track record of the Thomas Young Centre, The London Centre for the Theory and Simulation of Materials, in terms of community, industry engagement and training to ensure that this Hub eases the barriers for new entrants to the field and serves the UK MMM community as a whole.