Structural studies of uranium and lead compounds

The goal of the current project is to investigate crystal structures of uranium and lead compounds of environmental and technological importance. It includes two research directions: (i) design and study of new porous uranium materials in which uranium atoms are linked into three-dimensional frameworks via organic molecules of various shape and length; (ii) study of lead silicates as important phases that occur in nature and form as a result of lead mining and smelting. A detailed knowledge of the crystal structures of these compounds is important for understanding their occurence in natural and technological environments and for our ability to eliminate potential danger caused by the release of radionuclides and lead into the biosphere. The solution of the aforementioned tasks is to be achieved by means of state of the art X-ray diffraction instruments such as diffractometers equipped with Imaging Plate Detector Systems of the type recently installed at the Institute of Mineralogy at the University of Innsbruck. The research within this project is related to the problems of safe disposal of radioactive waste and heavy metal environmental pollution which are one of the most challenging problems of modern society. Many of the radioactive waste materials are unstable under oxidizing conditions and their alteration represents potential danger to mankind if actinides and radionuclides are released into the biosphere. Artificial barriers consisting of materials of high porosity may prevent escape of radionuclides into the environment. Design of such materials is one of the directions of the project. Environmental pollution by heavy metals is another important problem of modern industrial states. Such elements as Pb are very toxic and possess a number of serious health effects. Bioavailability and transport of these elements in the biosphere is controlled by the stability of their compounds under environmental conditions. In the project, some environmentally important Pb compounds will be investigated.