A semi-empirical simulation methodology to study exciton processes in glasses

We present a tight-binding simulation methodology embedded in a molecular mechanic approach and coupled with a two-particle time-dependent Hamiltonian to study electron-hole pair formation and decay processes. The method is nearly pairwise additive that makes it useful for-large scale simulations. Unlike classical potentials, the model contains electronic degrees of freedom that allow the calculation of excited states, homo-lytic and hetero-lytic dissociation pathways, and describes equally well the bulk, surface and cluster states of a networked system. We present the methodology, containing the coupling to a time dependent Hamiltonian, and discuss results that validate the model. (author)