Crystals are often described as brittle and inelastic solid materials that easily break under application of mechanical force. But nowadays, it is known that there are single crystals that can flex elastically or plastically when exposed to external mechanical force. This diploma thesis presents synthesis of coordination polymers of cadmium(II) halides and 3-nitropyridine; [CdCl2(3-NO2py)2]n (1), [CdBr2(3-NO2py)2]n (2) and [CdI2(3-NO2py)2]n (3). The compounds were prepared by classical solution synthesis and liquid diffusion. They were subsequently characterized by infrared spectroscopy, thermal methods and powder X-ray diffraction. Molecular and crystal structures were determined by single crystal X-ray diffraction analysis. Crystal structure analysis revealed the importance of intermolecular interactions (especially hydrogen bonds) in linking polymeric building units. Mechanical responsiveness of needle-like crystals, 1− 3, was further tested, and it was observed that needle-like single crystals of 1 and 2 are exceptionally elastic, while crystals of 3 are brittle. The correlation of supramolecular structure and observed mechanical behaviour disclosed that the more influential intermolecular interaction (and the more isotropic, in the orthogonal directions to the elongation of the crystal itself, they are) the crystals displayed the more pronounced elasticity.