Ferrimagnetism in the organic polymeric Hubbard model: Quantum Monte Carlosimulation

The ground-state properties of organic polymers are studied by means of the quantum Monte Carlo simulation. The polymer doped by transition-metal impu rities at every other radical site of the chain is described by the quasi-o ne-dimensional polymeric Hubbard chain. The topological structure of the ch ain possesses a flatband structure of the energy band. The spin-spin correl ation function and the static magnetic susceptibility are investigated in t he case of half filling. Our analysis shows that the on-site Coulomb repuls ions in the chain and/or in the radical lead to the coexistence of ferromag netic and antiferromagnetic order, i.e., the ferrimagnetic order. The on-si te Coulomb repulsion (U-d) of electrons at the radicals plays a more signif icant role in stabilizing the ferromagnetic order than that (U) on the chai n does, while U has a stronger impact on the antiferromagnetic order. [S016 3-1829(99)04205-8].