Metaboric acid "HBO2" or BOOH crystallises in three polymorphic forms - monoclinic, orthorhombic and cubic with structure features ranging from discrete units to a fully 3D connected zeotype framework. The hydrogen bonding in these materials, including a very strong unusual asmmetric hydrogen bond BO..(H).....OB of 2.48 Å in cubic metaboric, is central to defining the polymorphism. This experiment will cover the structural chemistry of these materials, the nature and role of the strong hydrogen bond in cubic metaboric acid as a function of temperature and the uptake of small molecules into this material. Materials will be studied as 11B isotopic samples but as hydrogen forms due to the need to understand the H-bonding.