This proposal seeks to exploit and expand on two recent breakthroughs. Firstly, a new class of bridging ligand will be used to connect metal atoms together, producing revolutionary new materials in which the sizes and shapes of the cavities and channels within them can be expanded and contracted in response to the presence and nature of specific guest species. Secondly, a remarkable series of multifunctional molecular nanoballs will be investigated thoroughly. This work produce novel porous materials which have applications in areas such as gas sorption (including hydrogen and methane storage, and carbon dioxide adsorption), catalysis and molecular sensing, and new nanosized molecular switches.