Spin-orbital correlations for t(2g) systems in 4d(4) configuration

We analyze the ground state configurations that emerge out of the competition between the static octahedron distortions and the local Coulomb interactions for a two-ion t(2g) system with 4d(4) configuration. By means of exact diagonalization techniques, we determine the possible charge, spin and orbital patterns as a function of the different microscopic parameters. In the specific, it is studied the role of crystal field as a suitable tune of the relative charge distribution between different orbital sectors, and a quantum control of the magnetic and orbital correlations. (c) 2006 Elsevier B.V. All rights reserved.