Spin and charge ordering in the dimerized Hubbard model

We study the effect of a chemically or deformation-induced charge-density wave on the spin-density-wave ground state of the Hubbard model at half-filling. We also consider the effect of a lattice deformation associated with a dimerization of the hopping term, thus introducing a competition with a paramagnetic bond-alternating phase. The slave-boson approach is used as an interpolation scheme to treat the electronic correlations from weak to strong coupling and determine the phase diagram of the model. We also apply our results to describe the neutral-ionic transition in organic mixed-stack donor-acceptor crystals.