Electronic rearrangement density matrix treatment

D. A. Micha. Density matrix treatment of electronic rearrangement. Adv. Quantum Chem., 35 317, 1999. 

A formulation of electronic rearrangement in quantum molecular dynamics has been based on the Liouville-von Neumann equation for the density matrix. Introducing an eikonal representation, it naturally leads to a general treatment where Hamiltonian equations for nuclear motions are coupled to the electronic density matrix equations, in a formally exact theory. Expectation values of molecular operators can be obtained from integrations over initial conditions. 

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