Symmetric Group Approach to the Theory of Heisenberg Lattices

Symmetric group approach to the theory of Heisenberg lattices 

In cases where Heisenberg Hamiltonian matrix dimensions prohibit their exact treatment one can use for energy states which are predominantly antiferromagnetic, an approximate method based on the idea of forming bonds between different lattice sites. These bonds, or rather the wave functions formed for these bonds, are then allowed to resonate giving rise to the RVB method mentioned earlier. The RVB method is very useful, since not only it makes possible a treatment of lattices which are out of reach by 

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