In the past decade, advances in structure determination with electron microscopy of organic, beam sensitive, materials have been significant. The newly developed techniques, triggered by new... Show moreIn the past decade, advances in structure determination with electron microscopy of organic, beam sensitive, materials have been significant. The newly developed techniques, triggered by new microscope systems and new cameras, made it possible to acquire 3D structural information from these samples to a resolution which was impossible to achieve before. Knowledge is required to improve structure solution and every aspect of the process involved, from treatment of radiation sensitive materials, sample preparation, TEM imaging and diffraction systems all the way to how data must be interpreted. In this thesis I explained multiple new techniques and methods developed by us, using both new microscopes as well as a new type of detector: Timepix. I describe how these tools can help to overcome (what were) the most important problems and bottlenecks in detection of very low dose electron diffraction. Show less
Geometric frustration occurs when local order cannot propagate through space. A common example is the surface of a soccer ball, which cannot be tiled with hexaganons only. Geometric frustration can... Show moreGeometric frustration occurs when local order cannot propagate through space. A common example is the surface of a soccer ball, which cannot be tiled with hexaganons only. Geometric frustration can also be present in materials. In fact, geometry can act as an instrument to design the mechanical, optical or physical properties of fluids and solids. The first two parts of this thesis discuss frustrated liquid crystals confined to droplets of various shapes and sizes. The droplet shape determines the orientation of the liquid crystal molecules and in turn its response to light. In the final part we study the fracture mechanics of curved elastic plates. By tuning the curvature of the plate, the critical length at which the crack starts growing can be controlled. Finally, we find that the path that the crack takes depends on the curvature. Show less