MAGNETIC POLYMER-CHAINS - A HUBBARD STUDY

Molecular or polymeric-based magnetic materials have been the subject of increasing interest in recent years. Organic magnetic structures ha ve been theoretically predicted by Ovchinnikov. One of the most attrac tive features of these new materials is the possibility of combining m echanical, electrical and/or optical properties of organic materials w ith magnetic properties. In the present work, we study a class of one- dimensional chains with special topologies that could lead to magnetic order. Using the Hubbard model, we find that these materials should e xhibit ferrimagnetic ordering at half-filled band, in agreement with a theorem by Lieb. Away from half filling these systems display a rich magnetic phase diagram.