Many-body Hamiltonians Hubbard model

We first study the electronic spectrum of a single C o molecule and then use the resulting low lying many-body states as the basis for an effective Hamiltonian that describes the physics at length scales larger than the size of the molecule. We begin with the simplest possible model of the one-electron spectrum and the simplest possible electron-electron interactions, known as the Hubbard model, but defined on the truncated icosahedral C o lattice. The... 

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