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Introduction to Solid State Chemistry (Dr. Sam Chong) •Basic concepts in crystalline solids (builds on CHEM111) o What is a crystal? – lattices, unit cells, symmetry o Describing crystal structures – fractional coordinates, Miller indices o Close packing of spheres in metallic solids o Simple ionic solids derived from close-packed structures o Rationalising structure types using radius ratio rule, and its limitations •Diffraction characterisation of crystalline solids o Interference of waves, Braggs' law o Concept of the reciprocal lattice, relation to the direct lattice and diffraction o Diffraction intensities and systematic absences o Experimental aspects of X-ray diffraction and uses of powder X-ray diffraction (PXRD) o Application of concepts to indexing PXRD patterns and deducing lattice centring o Limitations and complem
entary experimental methods (scattering, spectroscopy, imaging and microscopy techniques) •Solid state structures of functional inorganic materials o Structure-function relationships and applications of functional solids o Polymorphism - concept and examples in ionic solids, contrasts in physical properties o Spinels - normal vs. inverse structures and contributing factors o Perovskites - use of tolerance factor to predict perovskite distortion o Covalent solids - properties and structures of carbon allotropes o Framework solids - structures and properties of zeolites, metal-organic frameworks •Introducing complexity o Hybrid structures (MOFs, hybrid perovskites, fullerides) o Structure of the YBCO high temperature superconductor as a perovskite superstructure o Structure of point and extended defects o Doping, non-stoichiometry and disorder o Influence
of defect structure on functional properties and applications (examples from ionic conduction, MOFs) o Methods for the characterisation of defective and disordered solids; pair distribution function, transmission electron microscopy Electronic and Magnetic materials (Dr. John Claridge) •Synthesis of inorganic solids o Compare polycrystalline and single crystal samples and the advantages and disadvantages of their syntheses o Outline methods for synthesis of polycrystalline samples o Consider the difference in experimental conditions required for direct synthesis in the solid-state vs. in solution o Develop overview of single crystal growth methods •Electrons in Solids o Qualitative description of distinction between metals, semi-conductors, and insulators (atomic vs. molecular electronic structure) o Density of states and Fermi energy, and experimental evidence for these concepts
o Conductivity (Carrier density and temperature dependence) o Electronic structure of simple metals and transition metals o Band gap manipulation (Semi-conductor doping / Silicon vs. III/V systems) o Mott-Hubbard insulators and the breakdown of the band model •Introduction to magnetochemistry o Introduce the concept that solids contain magnetic moments that interact with one another in a variety of different ways, giving rise to a diverse range of exciting and useful bulk materials properties o Describe several key manifestations and applications of magnetism as well as compare orders of magnitude of magnetic field strengths o Familiarise with units of magnetism •The origin of magnetism in materials o Revisit spin and orbital angular momenta and their relevant quantum numbers and magnetic moments o Introduce the Bohr magneton as a convenient unit for atomic magnetism •
Magnetic moments of isolated atoms or ions o Describe the coupling of spin and orbital angular momenta and revise Hund’s rules to arrive at ground state magnetic moments and term symbols of rare-earth ions o Describe the effects of crystal fields and orbital quenching of magnetic moments of 3d transition metals to arrive at a spin-only formula o Compare calculated and observed magnetic moments of rare-earth and transition metal ions •Magnetisation and magnetic susceptibility o Classify diamagnets and paramagnets by the sign and temperature-dependence of their magnetic susceptibilities and compare some common materials o For paramagnetism, demonstrate Curie’s Law and how – through the measurement of bulk magnetic susceptibility – we can determine the atomic magnetic moment of a material •Magnetic interactions in the solid state o Compare ferromagnetic, antiferromagnetic and ferr
imagnetic states, with examples, that can be produced via magnetic interactions o Consider the energy scale of the dipolar interaction to show that this is too low in energy to account for the high-temperature magnetic order observed in many magnetic materials o Describe the concept of exchange to derive the Heisenberg Hamiltonian. Outline how exchange can occur directly, but more frequently indirectly through the indirect superexchange mechanism o Make use of orbital overlap diagrams to show how 90º and 180º bonding interactions lead to ferro- and antiferromagnetic orders, respectively •Measuring magnetic order in solids o Give an overview of magnetometry techniques and the capabilities for measuring magnetisation at the University of Liverpool o Describe how neutrons are very useful for studying magnetic materials •Introduction to multiferroic materials o Introduce the concept that coupling th
e order of spin, charge and lattice degrees of freedom in materials presents a major grand challenge in modern solid-state chemistry research o Define the concepts of ferroelectricity and ferroelasticity in analogy with ferromagnetism and detail the technological importance of coupling ferroic orders of solids
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