Solid State Inorganic Chemistry

We aim to understand and exploit the factors (strain, composition, band structure etc.) that determine structure and function in the crystalline solid state. Our interest is in the balance between local crystal chemistry, strain and longer range order in a wide range of compositionally and/or displacively flexible crystalline solids. The principal experimental research tools used are solid state synthesis, transmission and scanning electron microscopy in combination with powder and single crystal diffraction. On the theoretical side, group theory, lattice dynamical calculations and bond valence sum analysis are the principal techniques employed. Crystalline systems investigated include wide range non-stoichiometric solid solutions, displacively flexible framework structures, ferroic phases and phase transitions, solid electrolytes, dielectric materials and incommensurately modulated structures. Achievements over recent years include the first coherent view of the crystal chemistry underlying the phenomenon of ferroelectricity within the Aurivillius family of displacive ferroelectrics, the use of compositely modulated structure formalism to understand “infinitely adaptive”, non-stoichiometric solid solutions, and the discovery and subsequent modelling of displacive flexibility and its consequences in the silica polymorphs and various zeotypic microporous molecular sieve materials.