Competition Between the SDW and CDW in Quasi-One-Dimensional Organic Polymer Ferromagnet

The next-nearest-neighbor hopping interactions of pi-electrons in quasi-one-dimensional organic polymer ferromagnet are considered by Peierls-Hubbard model, and a see of self-consistent equations are established to optimize the system. The competition between the SDW and CDW states, which is determined by the interplay between the electron-electron correlation and the next-nearest-neighbor hopping interaction, is studied. At the CDW state, the SDW along the main chain will be tuned by the CDW. Consequently the ferromagnetic state, in which all the spins of the unpaired electrons at side free-radicals are arranged parallelly, will be no longer a stable ground state of the system.