Ligands containing aromatic nitrogen heterocycles play a thin the pyridyl rings. The complexes with these hard metals are close-contact ion pairs. In the indium complex 3 the cis-leading role in the molecular self assembling processes that lead to macromolecular architectures. The inductive effect of cis orientation gives rise to a dimeric structure, while the unprecedented cis-trans arrangement in the thallium com-various metal fragments on those building blocks has not yet been studied systematically. To evaluate this effect we syn-pound 4 leads to a polymeric structure. The complexes 3 and 4 have to be regarded as separated ion pairs of Me 2 M + ca-thesized the homologous series of Group-13 metal complexes [Me 2 AlPy 2 N] (1), [Me 2 GaPy 2 N] (2), [Me 2 InNPy 2 ] 2 (3), and tions and Py 2 N Ϫ anions without any covalent bonds between the anionic moiety and the dimethylmetal cations, even in [Me 2 TlNPy 2 ] ϱ (4) (Py = 2-NC 5 H 4 ), and characterized them by low-temperature X-ray structure analysis and 15 N-NMR the solid state. The series of complexes proves the bis(2-pyridyl)amide to be an excellent self-adapting ligand. These spectroscopy in solution. The electronic equivalence of the central and the ring nitrogen atoms leaves the energetic hy-findings are substantiated by NMR-spectroscopic studies in solution. Not only do the steric requirements of N heteroaro-perface of the anion quite flat, and the electron density is polarized according to the requirements of the metal. In the matic ligands have to be considered in molecular self-assembling processes but also the inductive effect of the diffe-aluminum and the gallium complexes 1 and 2 the metal center is coordinated exclusively through the nitrogen atoms wi-rent metal fragments.