Kondo Chains and Magnetic Clusters

The Kondo-lattice Hamiltonian conserves total spin and being an interacting model is nontrivial to solve. However, as with the conjugated systems, it is possible to solve finite Kondo chains efficiently by employing the VB method. The VB 

We see that additional orbitals or spins can readily be introduced in quantum cell models. The real constraint is the total number of orbitals, which governs the 

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