Ecuaciones de Bloch Ópticas en Sistemas Complejos con Acoplamiento Intramolecular

We propose modifications of the conventional optical Bloch equations for a complex system, when we consider intermolecular coupling effects. We model the isolated molecule as Born-Oppenheimer energy curves consisting of two-electronic states described as harmonic potentials, with minima displaced in nuclear coordinates and energy. We consider two-vibrational states and we include non-adiabatic effects for this two states model. Inclusion of a residual perturbation H, which may arise from a residual electron-electron correlation and/or spin-orbit coupling terms in the Hamiltonian of the system, may couple the above electronic states, causing the separation of the two curves according to the avoided-crossing rule. The extended equations of optical Bloch allow to establish the dynamics of a molecular system of adiabatic states subject to the interaction of a thermal reservoir and interacting with electromagnetic fields. The equations show that by making the intramolecular coupling factor zero, the conventional optical Bloch equations are recovered for a molecular system with harmonic potentials whose minima are found in exactly the same nuclear coordinate subject to the Born-Oppenheimer approximation.