Design of molecular wires based on one-dimensional coordination polymers

The authors report the results of ab initio calculations for the structural and electronic properties of one-dimensional coordination polymers with the general formula [M(6-MP)2]n (where 6-MP=6-mercaptopurinate, and M=MnII, FeII, CoII, NiII, and CuII). A common stable structure, consistent with the experimental data for [Cd(6-MP)2]n, is found for all metal cations studied, with the exception of MnII. Polymers containing FeII, NiII, and CoII are found to be ferromagnetic semiconductors, while [Cu(6-MP)2]n shows a Peierls-unstable paramagnetic metallic phase that undergoes a transition to a ferromagnetic semiconductor one under small stretching.