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