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This contribution gives an overview on the different subjects treated in our group. One of our fundamental interests lies in the synthesis and study of low‐dimensional polymer and molecular solid state structures. We have chosen several synthetic approaches in order to obtain such compounds.Firstly, the concept of cutting out structural fragments from a solid state structure of a binary compound will be explained on behalf of BaI2. Oxygen donor ligands, used as chemical scissors on BaI2, allow obtaining three‐, two‐, one‐ and zero‐dimensional derived compounds depending on their size and concentration. Thus, a structural genealogy tree for BaI2 can be established. This method, transferred to alkali halides using crown ethers and calix[n]arenes as delimiting ligands, leads us to the subject of one‐dimensional ionic channels.A second chapter deals with the supramolecular approach for the synthesis of different dimensional polymer structures derived from alkaline earth metal iodides, and based on the combination of metal ion coordination with hydrogen bonding between the cationic complexes and their anions. Under certain circumstances, rules can be established for the prediction of the dimensionality of a given compound, thus contributing to the fundamental problem of structure prediction in crystal engineering.A third part describes a fundamentally new synthetic pathway for generating pure alkaline earth metal cage compounds as well as alkali and alkaline earth mixed metal clusters. In a first step, different molecular precursors, such as solvated alkaline earth metal halides are investigated as a function of the ligand size and reactivity. They are then reacted with some alkali metal compound in order to partially eliminate alkali halide and to form the clusters. The so obtained unique structures of ligand stabilized metal halide, hydroxide and/or alkoxide and aryloxide aggregates are of interest as potential precursors for oxide materials. Approaches to two synthetic methods of the latter, sol‐gel and (MO)‐CVD, are investigated with our compounds.In order to generate single source precursors for oxide materials, we started to investigate transition metal ions, especially Cu and Ag, using multitopic ligands. This has led us into the fundamental problematic of “crystal engineering” and solid state structure prediction and we found ourselves confronted to numerous interesting cases of polymorphism and pseudo‐polymorphism. Weak interactions, such as π‐stacking, H‐bonding and metal‐metal interactions, and solvent, counter ion and concentration effects seem to play important roles in the construction of such low‐dimensional structures.Finally, the physical properties of some of our compounds are described qualitatively in order to show the wide spectrum of possibilities and potential applications for the chemistry in this field.

Varying the polyethyleneglycol spacer between two (iso)-nicotinic groups of the ligand systems, a large structural variety of silver coordination compounds was obtained, starting with zero-dimensional ring systems, via one-dimensional chains, helices and double-helices to two-dimensional polycatenanes. Theoretical calculations help to understand their formation and allow predictions in some cases. These structures can be tuned by careful design of the ligand, the use of solvent and the counter ions, influencing also other important properties such as light stability and solubility. The latter is important in the context of biomedical applications, using silver compounds as antimicrobial agents.