Topics:PCG Portfolio

PCG – Educational portfolio

Crystal structures and their transformations

• Space Group Symmetry
• Symmetry lowering
• Structural phase transitions – Landau theory
• Representation analysis
• Tensors in crystallography
• Charge density
• Modulated crystal structures – Superspace group approach

Elastic properties

• Strain-stress relations
• Pressure effects

Bulk properties

• Thermal expansion in crystals
• Atomic displacement parameters: relationship with phonons and specific heat.

Magnetic structures

• Description of magnetic structures – propagation vectors
• Magnetic symmetry analysis – irreps and coreps
• Spin density determination with polarised neutrons.
• XYZ and spherical polarimetry applied to crystalline materials

Microstructure analysis

• Strain effects
• Particle size and distribution
• Stacking faults
• Texture

Diffraction methods

• CW neutron and x-rays
• TOF neutrons
• Energy dispersive x-rays
• Diffraction imaging – TEDDI etc.
• Time-resolved crystallography
• Crystallography under high pressure
• High-magnetic-field crystallography
• SX techniques: Laue, time-sorted Laue…

Data analysis

• Refinement of structural parameters –least square – Rietveld
• Direct-space methods – simulated annealing
• Single-crystal techniques – twinning

Instrumentation

• Diffraction geometries
• Principles of TOF/CW instrument design
• Detector technologies of X-rays and neutrons